Looks good for a first go mate!
Well done...
Longer exposures are the key to more detail... Spend a bit of time on drift alignment to get your polar alignment as close to perfect as possible.
The EM200 is capable of fairly long unguided exposures, provided your alignment is spot on..
As it is, your 20sec subs show no~little drift, next time try to stretch them out a little longer. say 30~40 seconds.. Experiment untill you have noticable drift.
Also, with shorter exposures, the more you stack, the better.. When I was unguided I'd do 40~50x 30~40sec exposures.. This helped, but nothing helps reduce noise like longer exposures.
Good going for your first image!
Alex