I'd really like to see Transmission Matrix and Rescue get a redo. We've been playing them locally for an upcoming event and I am not a fan. It isn't really fun to lose such a huge portion of certain factions, while other factions and certain Fatality L2 2W "not HI" are unaffected. The terrain effect is super unappealing for Rescue, and the mission is jammer central on top of that, which together lead to some really unenjoyable games on it so far. The fact that Transmission Matrix works the way it does when CB have decided that stealth hacker links are ok is quite baffling to me. +1 for no Xenotech or making the Xenotech rolls relate to your army or decisions in some way. +1 for standardizing rules - make every datatracker, every Designated target etc work the same in every mission. I think there's even one where the exclusion zone works differently or is a different size! +1 to season long unit buffs such as Bravery, but I don't support them as a way to 'fix' units that just aren't appealing on their own merits. +1 for that Difficult Terrain idea mentioned above. An alternative could let them ignore the burst modifier if they are inside the terrain. Big kudos for 'fixing' Decapitation, its a much better mission without the first order 5pts thing.
Agree on Rescue, but disagree on Transmission Matrix. Since both MO and IA have good killer hackers now, they are totally in that mission if they play intelligently.
Bravery needs to go. Full stop. If some MI are bad, it's because their individual design is flawed not because they are MI. They're LI that trade half of their second MOV (most of the time) for a small discount and some increased access to juicy gear and higher stat ceiling. If you do keep it, then make it incompatible with Fireteams at least... Landing Assistance needs to stay. Permanently. But move it to the core rules. Same as TAG Fatality L1! Best thing this season brought.
If anything I think more non linked MI are fine without Bravery (eg Intruders, Proxy Mk5s). Lots of pure MI links are pretty meh without it (Wildcats, Grenzers etc) and those are meh even with it. Its just the ones that already dont have the typical MI weaknesses (expensive for effect, slow, hard to deploy for best effect) that dont need it.
Another thing that could kick Medium Infantry to the next level would be Shock Immunity granted passively, instead of Forward Deployment +1. It would give them durability in a meaningful way over LI.
Mentioned similar idea in post #8 above (along with the reasons I didn't put it in the OP). I do like the idea of MI being a more proportional step in durability between LI and HI than they are currently.