spend more money on pre or power amp ?

if the pre can't comprehend the information the amp will never see it. make certain that the pre is of the highest quality and performance and then forget about it while you find a cable amp combo that works with your speakers...

If I were starting from scratch I would buy the best and most neutral pre amp and speakers I could afford (by reputation, mostly). These would be my baseline for further changes. Then I would find an amp that matched the requirements of the speakers and that gave me a sound I felt i wanted (presumably neutral). I would further tune my system to my sound preferences by selection of cdp and cartridges for turntables (and phono stages).

Get the best pre you can get, tube would be nice with your ribbons or a top of the line passive. I would do this first. I have read that the new Ampzilla amp is one of the best with the RM-40's. As you may already know, the RM-40's are not plug and play and need to be fine tuned by hand after you get set up with new amp so you will have to start over when you change amps. I am a vmps owner for 6 years now (super tower/r's) and may go with the RM-40's soon myself.

If you have a good system and you are still feeling harsh there is a very good chance that your room is the problem. Clap your hands and if it sounds harsh or reverbs try deadening the room out before you run and spend tons of money to upgrade your system.

In my experience, matching the amp to the speakers is critical. I would think that in the $10K range, personal preference will determine how much you spend on each. I'd spend as much as it takes to get an amp that works with your speakers, then get a neutral preamp that doesn't ruin what you have.