So more feedback.
Not having a working medium mech
really slowed down my early progression, I've now gotten the Centurion from doing the get the Argo from the moon pirates mission and it's my only medium mech still. I'd say I'm maybe 20 missions in now. It's gotten pretty grindy to the point that I broke down and spent 1.8 Mil C-bils on 2 more Shadowhawk parts from a Store to assemble a 2nd Medium - 150 Days repair time
I'm really tempted to rush the Weldry mission so that I get the Argo, but it seems like it would be a bit rough with a Centurion, Spider, Urbie, and a Panther 9R (my first real light upgrade to replace a Commando), so I'm going to have to wait out until that SH assembles at least.
As for the Evasions stuff I feel like I should revise my earlier assessment now that I have some Gunnery 5-7 pilots. Everything
but Light Mechs is perfect where it is, but I'm still mostly forced to either Melee or use Support weapons to hit lights. Otherwise I hit a cap of about 35% accuracy trying to hit Lights even with good Gunnery Pilots, unless the AI screws up and only moves 2 pips worth (which happens sometimes at close engagement ranges). I was expecting that at Gunnery 2-4 but not so much on now on my more experienced Pilots and it gets frustrating after a while. I had a fight on a desert map against 4 Panthers where half my lance could not get into Melee range and that was kind of a slow, peeling chunks of armor off kind of a fight with a lot of misses for my Urbie and Centurion.
If it is possible to tweak Light mechs only, I would maybe suggest knocking them a single Acc notch towards being easier to hit. Either by lowering the To-hit Mech size penalty by 1, or better by moving a second evasion pip to Ace pilot just for Lights if that's possible.
I'm going to try it some more (I've got 150 days to go on that Shadowhawk still) so I'll let you know if I change my opinion again.