Content:
More combined-arms units (battle armor, tanks). The Upgrade series has been very good about this, folding in 'Mechs and other units from minor products; it makes re-buying them a much less bitter pill to swallow (I'm looking at you, 3039), and even gives me a reason to pick up some others (3055u).
Writing :
Other than the typos, I'm fine with the current style. And yeah, I know how hard they are to hunt down and correct. Intimately.
Layout & Stats:
I'd like to see a mini-MUL and/or list of Quick-strike stats as an appendix to the TRO. I know it adds page count, but it lights up things that might not be immediately apparent: I'd also like to see variants explored a little more, rather than having to wait months or years for a new RS pack that may or may not actually materialize. Maybe not a full stat block, looking at what that does to the Omnis, but if there's an MUL-like appendix it can list off variants with their armor, availability and equipment.
Rules:
More Experimental tech that isn't just "wedge Clan gear in an IS chassis". There's a prejudice among many players against allowing any of the fringe designs, simply because so many of them are boring to play with and against. For every RVN-1X, there's a dozen AWS-11Ms. Also, now that we're revisiting the TROs from the ground up and a much later era - having all of the designs in a TRO use the latest and greatest (all IJJs, all XPulses in the Solaris 'Mechs) rather than a mix of proven and Newtech makes many of the designs - and the equipment - feel gimmicky (3050 was actually really good about this, with many designs having an advanced system or two, but still relying on, well, dependable tech, adding in the H-types to the classic Omnis, etc.).
Adding "Advanced" rules supplements to the RS packets is an excellent way of adding value - it's the entire reason I own RS:3055 and 3085. Having the advanced rules in the TRO, however, means more stuff to lug around. How is this different than the RS packets, or my suggestion above?
• The TRO should be providing background information, helping you build your games' story and your unit collection. It's what you want to know about the 'Mechs, their history, etc. But you don't take a Jane's on the battlefield. Adding an MUL-style appendix lets you know at a glance what you want to field, and why.
• The Hexpacks and RS packs, on the other hand, are play aids. If you need special rules to field something in the RS, having those rules to hand (instead of having to lug around Tac-Ops, Strat-Ops, and I-Ops to play a Terra siege with LAMs, say) makes it easier to play while not requiring extensive hunting through 3-6 books in the heat of battle. It lets you know how to field what you have, and it lets players dip their toes into the advanced/experimental rules without getting slammed with everything at once.
Art:
A variety of art styles. Having different artists show their own visions of 'Mech design makes it look more like different companies and countries are making them. (Incoming criticism): My biggest problem with 3060 and 3067 is how homogenous the art is, especially when some of the designs are just outright awful-looking. Putting 60 illos on one artist makes everyone more likely to crank out/wave through another Yeoman -6Y or Lobo. Likewise, the art in 3050 makes everything look like it's from the same army (are the checks the Star League's equivalent to D-Day stripes..? If so, why not mention it in the opening blurb? "This commemorative edition, showcasing the brave men and women who broke the back of the Clan juggernaut, displays them at their finest hour. The checkered pattern was a intended to aid fast recognition of "friendlies" from hundreds of units in the chaos of battle. Indeed, many veterans bear their honored "Mechty Checks" to this day").
Layout:
My favorite layout style is actually the current one, used in 3085/3050u &c.. Clean, clear, consistent, and easy-to-read. "Primary Factory" can be kind of misleading, however. I'd rather see that kind of info in the MUL supplement. It lets you add in more information we can use in campaigns (building games), without having to hork up another Objective Raids. On the other hand, it does restrict wiggle room for authors a little, even with the "this is a snapshot in time from a semi-reliable narrator" caveat.
My least favorite layout is the one used in the original 3050 (short paragraph, no organization, little information, and sketchy art).
After that, 3060/3067's "stat bar on top" and hard-to-read black text on dark grey backgrounds are also very bad. TRO Protos is a little hard to read, but not nearly as bad.
(Edit: fixed a formatting error)
