I'd try not to go any lower than 2,500 unless your on a dead flat road and not going to accelerate. Its hard on the bottom end and could shift the crank.
+1 on that! I have the 30 tooth pulley on my '10 and feel that's about the right RPM to prevent lugging.
Lifters often tick for the first 20 seconds after start up, and tick at idle when the oil thins out...No worries.
IMO, Yes lifters do often tic. But think about it, hdy lifters are not supposed to tic, if they tic they are bleading down too much and your valves are not opening all the way which on the '07 up with epa cams means the exhaust is held closed even longer causing more heat especially at idle. Im not saying the bike wont run that way and probably most never see a problem.
Me I change them out.