RE: Why (an Enya 11 CX D) Diesel?
Your findings mirror my expeience.
I was able to get a lower idle on mine ... around 2600 rpm ... but for reliability, a higher would be a wise decision.
A friend made a traditional tommy bar for me from a humble (now headless) metric socket head machine screw and a length of piano wire. I have not filed and sanded it with particular care so it looks a little "rough", but it works very well. There is also a home made lock lever for it, though the tommy bar shows no sign of wanting to "wander" while running.