I'm open to pretty much anything, but here's a few things I'd especially like to do sometime:
1) Published scenario books - I've always (only been playing BT for a couple years, so keep that in mind) had a soft spot for wanting to run through some of the actual scenario books (w/the exception of 1st Somerset Strikers, that book sucks, but maybe I should give it a try anyway). Books like Fox's Teeth, Snord's Irregulars & Rhonda's Irregulars, Sorenson's Sabres, Gray Death Legion & Day of Heroes, Black Thorns, Tales of the Black Widow and More Tales of the Black Widow, The Falcon and The Wolf, Operation Stiletto, etc, etc. There are just SO many of these scenarios that I've never played, and many of these contain at least 1 mini-campaign with persistent units as well. Of course, I'm especially fond of certain units (GDL) and getting the chance to play through their origins as well as their later exploits (Day of Heroes) would be awesome. Another advantage, I think, is that GM effort is reduced because force lists/maps/special rules/etc are all defined in the scenario. There's also a great opportunity to play scenarios across a wide range of eras in some of these books, as they often cover events from Succession Wars to FedCom Civil War. Of course, with the Black Widow books, that could even be extended to include Wolf & Blake taking us into the Jihad as well. Regardless, it be nice to finally use those books for more than fluff info. Considering that some of you have been playing far longer, this may be an unattractive option because you've already done it.
2) Jihad Chaos Campaign - Again, same basic thing here, I'd like to be able to say I've actually played through all those Chaos Campaign tracks that appear in the Jihad line of books. It'd be a little more restrictive (possibly) because we'd be defining a
Player Force up front (I wouldn't mind this being a canon unit, btw, as the unit's established history can even provide some guidance on what tracks/contracts we choose to pursue). It'd work well though because those tracks generally call for a certain percentage of the "Player Force" to be used, not the whole thing, which will leave players available for OpFor. At times, Objectives in these tracks can be knocked out quickly and the scenario finished, and since the next tracks are available for the GM to check-out, it would be easy to be prepared to setup and run the next one (although in most cases the players will have to pick from a few options of a next track, so the GM would need to be familiar with all potential options). We could potentially run a merc force through tracks covering the Jihad from September 29th, 3067 (DotJ) through November 23, 3076 (JHS: 3076) and beyond (I haven't got JHS: Terra yet). Easy to get rolling, established framework,
CURRENT timeline including many new units we might have never dropped on the table before, and also gives us the framework of a persistent force on a continual timeline (if that's what we're going for).
3) Jihad Turning Points - It might be hard to see how these really work for a campaign, as they generally include less than a half-dozen tracks on a very stretched out timeline, however there are a couple things I really like about them. There can be a lot of flexibility here for the players, as they could choose from a large list of canon units from which to build forces, and every player could choose from whatever unit they wanted (within reason, as we'd need players on opposing sides) and pick the mechs they wanted (maybe 5k BV canon units per person, max 6 units, minimum 4), similar to what I did for this scenario (
http://www.classicbattletech.com/forums/index.php/topic,65279.msg1624968.html#msg1624968). Although these tracks generally specify what units are recommended for the scenario, it only takes a little customizing on the part of the GM to get everybody on the field. And since these tracks are generally spread out over a few years, you could use the same forces each time (possibly with replaced pilots) or you could bring a different force each time, just so long as what you bring fits into the force construction rules that the GM has established in advance. Additionally, there could be a lot of variety, as you bring something different after a couple games, OR as we move to the next JTP and choose up all new forces. Again, we get these awesome publications from CGL and I'm definitely partial to putting them to good use. Unless I'm miscounting, we've already got 6 of these so that would keep us going for quite awhile as well as eagerly anticipating the next one. We'd also be contributing to CGL's development of these in a meaningful way as we playtest them, post AAR's and reviews. On the last campaign, there were times I definitely got very bored with my mechs (Hatamoto and Archer), playing the same two mechs week after week. In a JTP campaign, say we started with Luthien, I could pick from varied Drac, WoB, Ghost Bear, Nova Cat, or Merc forces, build a force to the size the GM has specified, use that force for all 5 tracks (or possibly only portions of that force), and then it's over and I'm on to picking a force out of JTP New Avalon/Dieron/Atreus/Sian/Tharkad and using something completely different. Sounds fun to me, ymmv.
So there's my pitch for playing through some published stuff. Like I mentioned, long-time players may definitely be opposed to option 1, since they've done it before. GM's may see this as too restrictive as well (I know Rob would say this), but a GM would constantly be adjusting the scenario to fit the group, making changes to keep things balanced or adding surprises and such to keep the players on their toes (especially with option 2 & 3). So, on to some other stuff...
4) Open Jihad Campaign - Standard sort of Player Force open campaign involving a merc/house unit (again, I wouldn't mind a canon unit). It's the current timeline, and there is tons of stuff in TRO 3075 that I still haven't gotten familiar with, not to mention 3085.
5) Planetary Conquest - Like what Phil suggested, something similar to the campaign that was being posted over on the CBT boards for a while. Have a couple Generals who move forces during each game "turn" (double-blind) and when forces collide, mayhem ensues. Split up the player base between 2 (or more) factions and go crazy with it. Lots of options and things you can do with this. Defining the campaign framework is the biggest obstacle, imo, but others have posted good rulesets already that could be adapted. Has the benefit of opposed forces, like Knightofaargh mentioned.
6) Interstellar Conquest - Same basic idea as #5, but a campaign involving taking and securing not just one planet, but multiple planets. Could potentially have two player groups working to control the most planets within a time-frame. Lot's of options here, any era works. Could also involve aerospace assets, ftw.
Anyway, takes me awhile to post something like this, because I get excited and quickly buried in the minute details that are possible, and then I realize that I'm not GM'ing it, so I strip that stuff back out and start over.
But the fact is that I like playing BT, so while I've got some ideas about what I'd really like to do, there aren't really any campaign ideas that I'm
opposed to, as long as we're not introducing aliens, or having a KF-drive misjump that results in arriving on Earth in the mid-80's and being required to save the whales.