Dont fly that 4* yet! Its a great plane...probly better 3rd plane. And by reading your post,your alot like me in that you put alot of effort and pride into your projects. So,its just not worth risking your 120+ hour plane in the air. It'll always be there hanging on your wall though till your ready for it,and by then it wont seem so great(which is actually a good thing). With that said.....my second plane was a big stick .60 and MAAAAN am I glad I chose it because it was likely the BEST second plane I could have picked. A .40 sized stick will be good too I'm sure. I definely go with something like it before you fly your hard worked 4*. Not that your 4* is much harder to fly.....its just that you got too much time in it to smash it with your experience or even if your plane would malfunction.....it would suck(trust me). Buy something quick to build,not too expensive to build,and one that isnt the coolest thing(this is the most important). Then if worse case senerio happens.........it wont be "as" bad.

And just a tip....its always a wise decision to have a good instructor maiden your plane and land it the first time or two if your not comfortable. He'll let you take controls a bit midway through the first couple flights. At least then if worse case senerios happen....you got SOME flight time with it. He might also crash it,but you have to tell yourself.."the chance of him crashing it are WAY less then me crashing it". And its always good to go with the odds in your favor. That way,if it gets smashed...at least you did all you could do and make the right decisions (theres alot of satisfaction is that alone).