What tweak, what to do?

Hi. First time on this forum. I need advice.

The very quick version of my question is: what makes a bigger difference to resolution, bass extention, etc., an decent equipment rack or isolation devices like the vibrapods or tenderfoot?

I have a limited number of $ -- around $200 tops -- to spend to improve my system. I have: Naim Nait 3, Naim Flat cap, Rega Planet, Rega Planar 2 w/super bias (that's got at least 1000 hrs on it), ProAc Sig Tablette 50's with custom stands, Sunfire True Sig Subwoofer Mk2. The flat cap has a crossover that diverts low hz signal to the sub. Odd set up, but, if well positioned, can be fantastic. But it's quite sensitive to set up. The gear is placed on a none to rigid coffee table, with the turntable on a separate side table. All are on carpeted cement floor in basement.

I love vinyl. One obvious thing to do is replace the cartridge with something much better (e.g., Exact, Dynavector 10x5). But I just don't have the $ to do that now.

Another is to get an equipment rack. I can maybe get a used one -- perhaps a Standesign design 4. That will give better isolation to the whole system. (By the way, is it ok to put the t-table on the top shelf with other electronic below? or is it imperative to have a separate support for the 'table?) On the other hand, that would eat up the whole budget, and i wonder if I cant get as much or more benefit from a couple of sets of cheap isolation devices for under the CD player and t-table, and have a few $ left over for other tweaks -- such as herbies t-table mat and grungbuster (comments on these?.

Too many options, not enough $ or information. A chronic problem with a million faces.

Thanks for the input.

Richard M