I assume the giant "dome cockpit" of a Mad Cat isn't all actually cockpit or the things'd be deathtraps. Is there a "sub-cockpit," in the centre of it?
I've been a bit torn on this issue because just aiming for centre-of-mass probably gives you the best chance of a safe hit if there's any lag, and also probably provides the best focus-fire with teammates doing the same thing. I've tried aiming for cockpits that are 'obvious' but had such mixed results that I'd given up. I sort of decided that mech-by-mech "cockpits" probably didn't match the visual appearance and I should stop wasting valuable seconds waiting to fire recycled weapons by aiming for 'glass.'
The way legs work seems pretty sensible. You can usually tell if it'll be a good idea or not. I tried legging a lighter mech during a circle-of-death and... well, I deserved to lose doing something that dumb. A missile-boat, though, or an assault/heavy mech taking a long slow walk? Great opportunity.
EDIT: Does anyone know, incidentally, how much damage a man-pack PPC does relative to the mech version, and if the range is still 700m? It's obviously still "powerful-ish," but knowing exact figures would give a better since of just how long you should mess around the battlefield after ejecting. If it's doing 1/3rd damage or less I'd be more inclined to hoof it back to base and grab a Harasser with spare change.
It's be nice, in general, to get a breakdown of weapon damage and mech armour, even if the devs wanted to leave a certain amount of "black box" game mechanics to foil munchkinism. As it is I'm kind of "guessing" as to the respective sturdiness of different mechs and the potency of different weapons. I might prefer the loadout of a Catapult to a Warhammer on a certain map, but I strongly suspect the Warhammer is the tougher mech... How much tougher? The actual variants on sarna.net actually are different depending on loadout and so on.
I don't personally really want a mechbay because I think it'll lead to FOTM-boating, but I know it's what people want. Given that we're eventually going to be in munchkin heaven anyway, it'd be cool to have some more numbers for armour and weapon stats. (How much tougher is a Kitfox than a Raven, eg)