I'm not going to chime in about how it would look to a potential employer, looks like you already have a good answer for that.

What I would caution you to do is, pick up a trade-a-plane, look around your local FBO's, or go to controller online and find a Cessna you could buy for around the $10,000 - $15,000 range that has some time left before TBO rather than lease. Then you are just paying your hourly gas bill.

I doubt anyone will lease an airplane to you for massive time building without requiring you pay a premium hourly cost. The reason is that no one that has set out to sell an airplane (typically) wants to lease the same airplane to someone that is just going to rack up the hours on their engine unless it is just impossible to sell (and if that's the case, you probably don't want to fly it). As cheap as you can buy a Cessna right now, it doesn't make sense to lease one for that ambitious amount of flying time. In this scenario, you can resell the airplane when you finish with it, or keep it and enjoy flying it with your Grandfather and family.

Either way, run the numbers on the lease which will probably come out slightly less than a dry hourly rental from an fbo and compare it to the cost of buying before you get too far into a lease discussion with someone.

Sounds like fun though - good luck!