Truly awesome work man. I've had this as my desktop background for a while now, and almost every single time a coworker has come over to look at something on my screen they excitedly ask me what game this is from. Considering that we work at Firaxis Games and with all our experience thought this could be real, I really think this game would have a real shot at making it! A few of them even thought it was a screenshot rather than a concept before they looked at it closely.
You may joke about needing the money to do it, but if you worked with a decent 3D artist and programmer I bet you could put together a small demo you could pitch to publishers to get the funding you need. There's a number of people who have gone that way lately because it is easier than ever (since everyone can use UDK or Unity or now CryEngine 3), and it's actually the same way one of my personal game industry heroes got his start: Fumito Uedo, who came up with Ico and Shadow of the Colossus.
So I hope you pursue this as a real project! Good luck!
Always loved this pic! It could be taken two ways: a new MechCommander / strategy game, or a twin stick shooter like Gattling Gears / Renegade Ops (more akin to the old "Mechwarrior 3050" game on Genesis / SNES), but much slower paced, more tactical, easy to pick up and play but with enough depth for people that want it, with tower defense elements and Mech customization - it's a concept that imo would sell well both on PC and console digital download services, priced at 10-15 dollars.
There's always the option lots of people do - develop a small proof of concept prototype, and pitch it to publishers. Even Smith & Tinker and Piranha Games, the guys doing the MechWarrior reboot, did this, they built that 3 minute teaser video and went around looking for a publisher / money.