TOTO, Welcome to RCU!

What you suggest is not impossible by any means. What I would suggest is: Once you are proficient with your trainer, Slap a SPAD together (If you're not familliar with SPAD, it stands for Simple Plastic Airplane Design) RCU has a forum dedicated to SPADs. They are increadably cheap (About $10 -$20) and damn near indestructable (They are made from the type of corrogated plastic that Election Signs are made from, just "fold and Fly")

That will give you some stick time with something other than a trainer, while you're getting the Cessna ready.

Once the Cessna is ready, have a good flyer take you up with a buddy box for the first time just to keep you at ease until you're confident you can do it. Once the butterflies go away, you really shouldn't have a problem.

Good Luck!