1) Really cool. I like the use of budget mechs like the Storm crow and Mongoose. The Undines are an interesting choice and Svantovits are probably going to be very good for the objective-based games with their 20+" move.
The Battle Star is a great choice no matter what, because Lucky is amazing. I don't know how much I like that many skill 5 units myself, but if that's something you're comfortable with, more power to you.
2) Yeah, since you have 12 or less units you get to assign 1 unit SPAs as described. The Awesome or Masakari definitely seem like they'd be the best picks since they'll stay around the longest. Skill 3 units get 2 SPAs totally 4 points or less, so might recommend Weapon Specialist or Tactical Genius alongside Human TRO or a point of Lucky.
3) It doesn't seem like you have a whole lot of units in this force that can reliably deal TMM4 units that can take a hit in a significant way. For your defender list, I might suggest trying to lock in a unit or two with skill 2, something with artillery attacks, or the AC, LRM, or FLK special to either combo with SPAs that reduce your to-hit number like Sandblaster, or to capitalize on Alternate Munitions like Precision Ammo.
