Hi Ian, as others have said here,there are a number of factors effecting your viewing and all well explaned.
The seeing wasn't that great tonight untill about 10:30 here but even then it was just average.
Higher mag in a smaller scope will degrade the view taking in all the factors mentioned by the other guys.
Look forward to you getting better and you getting out here and giving your scope a real good workout under a dark sky.
Cheers