Pound Puppies is now done by the same animation studio and some of the same staff. It looks OK I guess.
To be concise, ponies are easier to get into as a following because the main characters and world are better sketched out and lend themselves to fanmusic, fanart, games, ask blogs, events and so on.
The show's music is really stand-out as well.
Subjectively I prefer the animation and writing of MLP to the other shows. I find in particular Strawberry Shortcake assumes it only has a young audience, whereas ponies tries to be smarter than that.
We have a pony thread for this kind of question. I'll answer in more detail if needed.
http://gamrconnect.vgchartz.com/thread.php?id=141117&page=207