I personally prefer to see Ebert on the wing. He's an elite winger, however in the centre he just makes too many errors.
I think Toumpas has done enough this pre-season to get a spot on the interchange for round 1, probably will have to wait until round 3 though (I was really impressed with what I saw from him in the 2 NAB games - I think he will be a trading steal in retrospect) - tough to fit him onto the field though, shows promise on the wing and half-back flank and we already have better (i.e. most prominent) players filling those roles.
Fantastic side on paper, hopefully they can deliver their potential this season and take full advantage of the favourable early fixture