The Sig SSE would make a great first kit and 3'rd airplane and would be my recomendation. It does only come as a .40 size though like you mentioned. You may want to consider the SSE anyhow. It's almost a "must have" airplane at some point.

If you really want a .60 size airplane, I suppose the GP Extra would fit the bill or maybe the Sig Hog Bipe? The Hog bipe builds similar to the SSE and 4* other that the extra wing and stuff that goes along with it.

The Ultra Sports are reported to be great Sport/aerobatic/pattern type planes. Mine is still in the box. It looks like a nice kit but is more "old school" in the way it is built than the SSE. Nothing wrong with that at all though.

Another option might be the GP Super Sportster 60. I built one and it is a step above something like a 4* in aerobatic performance but still forgiving to fly.