Suggestion 1
When you are in the Garage you have the option to remove the HUD and get a better look at your mech, what if you could also POSE your mech in one of the Arcade Victory Screen poses so you could get some cooler shots of your mech to show off to people.

Suggestion 2
This one is a little more touchy because it involves game balance and a weapons mechanic...  The Dominus Railgun Sword, a very cool weapon but it seems to be a hindrance with its "Hit the enemy to charge" mechanic. The 3rd Level Charge specifically you most likely never want to use due to how it locks you in place and drains your entire Boost Gauge, but you are FORCED to use that move should you get to the 3rd Charge severely limiting the weapons potential. Now it could be as simple as just "Just use it before you reach Lv3" but could be a total waste of the weapons Railgun shot or be impossible during some circumstances.
My Suggestion for its reworked Mechanic would be a "Hold Alt Fire to Charge" While you are holding the Fire Button the weapon will Slowly Charge enabling you to pick your moments but still make you commit, it becomes more usable but still offers the same risks of overcharging it.
Lv1 Would Charge relatively fast while Lv2 would charge slower and Lv3 even more so. You should also be able to use basic melee attacks while charging. Obvious damage adjustments would have to be made.
An Easier alternative Suggestion would be the make the Dominus Hilt bash lower weapon charge. 

Suggestion 3
Like suggestion 2 this is touchy as it pertains to game balancing. Currently with Guns it feels a little cumbersome to have multiple Gun weapons and is essentially just a Larger clip. This suggestion to Guns would be the ability to Fire MULTIPLE Gun Type weapons at the same time at the cost of rapidly expending Boost Gauge.