Rega upgrades/tweeks

I am soon to be the owner of a new P5, Exact II and seperate power supply. I know all about "not messing with the Rega sound." However, I AM curious re others experiences. Esp the Expresimo Heavy Weight and end sub, thanks.
I do, indeed. At my age I confuse terms sometimes, it is the groovetracer w/ruby. Every LP is another small adventure. I'm also learning the CRITICAL importance of keepting the stylus clean.............
Adding the Funk Achromat to my Rega P3 was the best thing I ever did to the deck, as it cleaned up the sound no end. The bass is more defined and the treble less harsh.
Over the years I have tweeked my Rega to the point where I now have a really nice detailed, tight, airy sound with excellent imaging

My turntable is a 25year old Planar II - the one with the melamine covered particle board plinth (Not a winner!) and the glass turntable with the non-rega arm

So here are my twweks:
1. get the RB250 arm (minimum)
+ Rega Elys cartridge (minimum)
2. get rid of the crappy Rega RCA plugs
- the wire is actually very good
- adding Furutech RCA's made a world of difference ($20)
- WBT silver solder ($20)
3. cover the melmine surface on the plinth with Cork ($5)
- reduces music induced vibrations
4. cover the underside of the platter with cork
- reduces music induced vibrations
5. install a Mission "sorbothane" turntable mat ($40)
- reduces music induced vibration
- reduces pickup induced vibration
- tightens bass
6. install a decent record weight/clamp
- a hockey puck with a hole that grips the spinddle works great($1)
- extends high end details
- increases image accuracy
- reduces pickup induced vibration
7. loosen the feet
- you should be able to rotate the foot freely
8. isolate the feet from the shelf using large glass marbles ($1.50)
- increases high end details and imaging
9. sit the deck on an MDF shelf in a decent rack
10. Lubricate the subplatter shaft
- in the sump: high viscosity gear box oil
- on the shaft: Duralube oil additive
- Duralube makes a huge difference - so quiet now

OK - I know some of them seem a bit weird, but they each work.

This turntable never was one of Rega's finest - the only good thing was the motor, bearing and platter - Oh, and the cover. So I had nothing to really to lose.

The glass marbles may sound hoakey, but they made an astounding difference, the deck appears a little "wobbly", but it is stable enough with the marbles under the rubber feet - you'll need about a 1 inch marble.

Best bang for the buck - the Furutech RCA plugs - try them before you re-wire the arm

My next tweek is to replace the plinth with one made of MDF - hoping to get rid of the cork look.

I think the end stub on those arms are OK (RB 700?). What you are looking for is a metal end stub that is very secure on the arm, so that it is essentially one piece and I think that arm already has that. Find out which of those weights can be used on the existing stub (if it's OK, i.e.- metal and rigid). You can definitely get improved bass with a better end stub. Groovetracer subplatters are supposed to be excellent. They are well machined alloy subplatters, which should enhance the PRaT on that deck, but again look at what you already have. The marbles sound like a good idea. They're cheap and reversible, if you don't like it. I use pumice sponges under my Rega feet and they really opened up the soundstage. Rega's are very sensitive to the base material/shelf they are sitting on, so check that out. They(like their design)need a light and rigid platform to sit on. A wall mounted shelf is best, otherwise a light floor standing rack works well too. Check out Ken Lyon's posts on "vinyl asylum". He's been tweaking these decks for years and seems to have squeezed every last drop of PRaT out of them. Even stock, they are a ton of fun to listen to when they are set up correctly.