If you haven't seen it already, check out MechWarrior: Living Legends here: http://www.mechlivinglegends.net/

This Crysis: Wars mod has various Tanks, Mechs, Vtols, and Aerospace Fighters of both Innersphere and Clan variety. The Crysis Nanotech Suit has been replaced with the Elemental (Clan) and Longinus (IS) BattleArmors, complete with SRM packs and Small Lasers, and of course, jump jets.

Here's a Video of some gameplay: http://www.youtube.com/watch?v=R1w5xBk9B1E

The video does not do the mod justice however since it is from version 0.2.0 and they are now on version 0.4.9

The mod is still in Beta but it runs extremely well (assuming you have a computer that can run Crysis.. and then some). By far IMO it is the best MechWarrior game I have played yet. The MechWarrior Reboot would do well to take notes from this mod.