Well EG Movies are spin-off than a normal MLP and why Equestria Girls was made? - Because Hasbro want to make new products and toys to tell I dunno if pony toys are selling better than EG dolls so that's why they did EG. (New toys)
And I think EG is better than MLP because.....it's better.
Well did you watched Rainbow Rocks, Friendship Games and LOE already?
If not check it.
Well that's all I wanna say I dont know if this helps ya or not.
Have a nice day!