New owner of a 2008 Torrent (Base model with the 3.4L) -- I just bought the vehicle for my daughter for her 17th birthday. It needs some work of course (that's why I'm here naturally :-) ). It has about 190K on the odometer (purchased from original owners) and has had fairly regular maintenance done on it (including the infamous intake manifold gasket and head gasket job, early on in its warranty coverage period). I will be getting underway on it in a couple of weeks to get it tuned and road-ready (valve cover gaskets, oil filter housing gasket, plugs, wires, air filters, TB clean, AC recharge, new front and rear brakes, new front hubs, etc. I did notice on the drive home that the idle had a small bounce in it, one that could only be detected by looking at the tach needle bouncing ever so slightly. The engine runs super quiet (can hardly tell it is running) and is very smooth. But I just want to get an idea of what possible culprits (usual suspects) like to cause the bouncy idle on this engine (no check engine lights by the way). Intake manifold gasket leak (small), evap leak, vacuum leak, dirty TB, MAP, plugs, wires, etc.
I am also wondering what items are common replacement recommendations prophylactically on these.

Thanks in advance