Cannot find a dedicated thread covering something this important, so I'm going to start this off with my take that I hope helps newcomers and those like me who always find useful info here. Apologies if already done.
1) Position – NOT hard up against the wall if possible, as I found with my first lathe.
I wish I had not done so with the Emco V10P, as it did not have a splash back meaning that some of the swarf ended up on the floor between machine and wall, and access to the motor was impossible.
Never occurred to me to make a shield
too busy with making things and running the shop 
My Warco BH600G, on the other hand, on a reinforced factory stand and raised 6" (150mm), is at an angle to the wall with Headstock 10" (254mm) away.
This givies me easy, albeit cramped, access to the rear of lathe, and enabled me to fit the 3-phase motor quite easily. (needed a week to unbend myself, but heck it's part of the fun!)
Also, with the Tom Senior being within spitting distance, the angle allows long material to be fed through the spindle if ever needed.
It does of course depend entirely on the space available, and where the lathe is positioned.
2) Spindle height – Mine is 50.1/2" (1.28m) from the floor.
I stand on a 5" (127mm) high duckboard. I learned a hard and painful lesson from having to bend over to work on the Emco.
I can easily make a lower duckboard if needed, compared with the much much more difficult task of raising the lathe.
3) Lathe stand – As solid as possible goes without saying, with adjustable lathe hold-down bolts being an absolute must.
4) Motor – Fit a 3-phase motor with VFD control if finances allow.
Most new lathes appear to come with finger twiddling speed control nowadays though.
Fitting one absolutely transformed the BH600G and with luck the FeedRod mod, when done, will do something similar.
5) Lighting – As much as possible.
I have one of those IKEA flexible LED lights pointing at the chuck and being easily repositioned having a bulldog style clip at the end.
Enough from me, so over to the Collective for any other suggestions/recommendations/experiences?
Geoff – In recovery mode from gardening yesterday