I'm in favour of Companies being the building blocks of ground forces. I love the idea of 'Command Sizes' not being unit based, not the least because I can finally build 'triangular' brigades & divisions without feeling like I'm wasting capacity.
I like PDCs, I use them in all my games, though not all that much. I find the resoning "because they are exceptions to so much existing code, requiring hundreds of if PDC do X, else do Y statements to be 100% sufficient reason to dump them entirely. I will miss them, but not much.
The only two problems I have with PDCs are the instant-reload of magazines from planetary stocks (already fixed) and the maintenance-free status (including giant hangars & their contents). Since I don't use PDCs that way, it's not actually a problem for me.
I would prefer ground units use up Maintenance Supply Points for repair rather than Replenishment units, mostly because I like the elegance of 'everything uses MSPs'.
I don't particularly care if we call them Titans, Combat Walkers, Super-Heavy Vehicles, Air Cavalry, BattleMechs, Artillery, Organic Realtime Combat Synths (ORCS for short) or Kaiju. I'll be fenaming them to something appropriate to my Empire every game anyways.
Oh. I'd also really love a smaller version of a Construction Brigade. Maybe a Construction Battalion that was 1/10th as effective, and a Construction Company that was 1/50th. Since I usually play conventional starts, I frequently have the problem of "Oh, that's an interesting alien ruin. When I finally manage to build a Troop Transport big enough to haul a Construction Brigade there 22 years from now, it will be exciting to see what's in it."
Which reminds me of one other suggestion I have (entirely off-topic for this thread). I would beg Steve to rename 'Conventional' starts to 'Low-Tech(Hard) Mode' or 'Expert Mode' or something. It seems like every week a new player comes to the Academy forum saying "I chose Conventional start because that seemed easier, or more basic, or to be tutorial mode, and now I'm hopelessly lost."