As far as I know, the timing is ok. By that I mean it seemed to be all this time. The only noticeable strangeness now is the fluctuating idle. I'll plan to just do a basic valve adjustment and get the carbs right for now.
Yes do that BPT, that will put you on the right track.
Playing around with the idle speed and mix to balance the carbs takes time and patience, and unless you have a big fan to put in front of your bike to provide cooling you need to go for a ride, firstly to get the engine up to normal operating temp, then riding inbetween adjustments, to cool the engine (as you will keep it running while adjusting and listen to the exhausts, trying to even the 'pop' so they are the same). I take a combination phillips head/flat head screwdriver and 10mm open end spanner (for the cable adjusters) in my pocket. As mentioned, Barry has posted a really useful link on the technical FAQ's board on carb tuning by ear:
http://www.bmwr65.org/YaBB2.612/cgi-bin/yabb2/YaBB.pl?num=1274863320If, after doing your valve clearances and playing around with the carbs, you still have a high idle problems then I'd look at squirting some lube in the bean can.
Any easy to notice symptoms that the timing could be off?
I've had to slightly adjust my timing once. Performance wise it was obvious, it was stumbling, not quite firing right, below 3500rpm, esp. noticeable after take off (fine) then holding speed at about 25-45 mph (stumbling).