I have this plane. The rudder is almost useless at slow speed, ie stall turns etc. A bigger stab won't hurt either. Just dont add weight! They are very much tail heavy with the 60 size engines. I removed a bunch of the balsa infront of the rudder I didn't think it did much.
I suggest building the fuse so that you could do the tail dragger conversion at some point. In fact I would build it that way to start. The nose gear I find is only really good at removing your firewall. They also handle better as tail draggers.

BTW it really is a great 2nd plane - you won't regret it.