Frisco -
When they re-felt, have them check your bumpers to see if they are glued on really good. Mine were replaced and one spot has a "fart" when the ball hits (not enough glue, or kids were pushing on them at one time). But I am too lazy to tear down that rail just for that.
When they relevel the table, let me know how they do it. My installer said all they do is measure with a 4' level, then one guy pushes up the table by the base platform, and the other one inserts coaster-sized shims under the feet. (Never lift or sit on the rails because it can break the rail or the slate, and according to my installer, the rails are the hardest to replace even though they are usually standard/common amongst most other tables in the lineup.)
If it were a Vegas game table, it would have to have a level mechanism built into the table for easy adjustment.