Decoration limit
I'm on an iPad 2 as well and have over 4800 in both SF and KL. The only bug/glitch I still get is crashing after visiting too many friends in a row.
Forum Discussion
You may want to search tstoaddicts, or just talk to Bunny over there. She has extensive experience with this. As I recall 10,000 or more. And several times she has had to get EA's help because of it.
