I mean no offense, but if you emailed me with this as a proposal I'd pass.
You've got a solid start to the engine, but at the moment I can't really see much of a plan behind it.
So let's get into it.
At the moment you really do have the basics, running, jumping and climbing.
First of all, they'll all require specific animations, then all those animations will require transitions such as landing, reaching the top of the ladder, turning around while standing/jumping etc.
then think about things like what if you get hurt while turning around, which direction will the players sprite revert to? Will the next time the player turns have the animation executed correctly?
For Twinsen we still don't have his movements 100% correct, there are a few small glitches that occur under specific scenarios that are tough to iron out.
Basically, you need to plan, plan, plan.
We started Twinsen with barely any plans, just about everything has changed since then, and I've had to redo pretty much everything at least twice.
It might seem easier just making it as you go, but it's much easier to have a comprehensive plan in the long run
And finally, about finding a spriter.
I think it's a bit premature to recruit anyone right now. It would take about 30 minutes to make original graphics for everything in your build so far.
When you have a complex and versatile engine I'd recommend the pixeltendo forums, just about everyone there is an amateur in highschool with plenty of free time, not everyone there is very good, but there's a handful of people with real potential.