Profile Hots
In the case of balsa, the MAN Profile Hots plan is a winner. It weighs about 3 lbs. ready to fly. The little .40 LA should pull that around well... Not much wood in it, either, so it's cheap to build...
I built mine with an OS .46 LA on it, and it would hang on the prop till it ran out of gas, if you so choose. I also put some 1/8" wire 'normal' gear on it, instead of that single wheel stuff, and it worked really well... I built mine in a week, from scratch, so you know it's an easy one...
good luck in your choices,
phil in austin