Utterly lost as to how to play. Desperately needs a tutorial :)
UPDATE:
Based on your feedback, I made the following changes:
A) Added tooltips for many important UI elements.
B) Updated mission tips to make them more clear.
C) Made it clearer how deployment works at the start of a missions.
D) Added tutorial messages for mission selection, mech loadouts, and the first level.
Check it out when you have the chance! :)