OK - I'll attempt a few..
1. Run the RPM at the level you need to get the job done - I usually run between 1500 and 1800 RPM seems to work for most jobs, but if a tough stump etc will up it to 2000. Higher RPM means it moves faster so 1500-1800 seems to run smoothest for me.
2. I leave it in gear - while sitting in the seat I can reach the HST pedal (
B21) and move the tractor around (you may not be able to do this with a larger machine) I dont think leaving it in gear will create too much stress either way.
3. Stablizers/Front Bucket - Most of the time I leave the FEL up and just use stablizers and dig, but if in tough digging rocks/stumps getting the bucket down first and raising front wheels then put the stablizers down makes for a much more stable digging platform.
4. Stumps - leave 3' for leverage on smaller 6-8" trees and dig around the stump some first then use that as a lever to break loose.
5. Rocks - get a thumb! and pick up and transport and place them in the BH thumb. Also in rocks be careful about stablizer cylinders - rocks roll and fall
6. Digging/Planting - when creating a hole for a tree place dirt around three sides and then level the spot in front or side so you know ground level - this prevents planting tree to deep or shallow.
Also when transplanting, get a FEL load of dirt/compost, dig the new hole then dig out the transplantee then backfill old hole with some dirt, then pick up tree/bush and take to new hole and install covering with remaining compost. This is more logistics than BH use I know..
Trenching - lots of different things here depending on each situation to straddle or work from the side and depth all are factors - I usually try to put the nasty stuff rock/roots on one side and segregate cleaner material or loam for backfill if you dont have sand for around pipes etc.