i just bought a used redcat RS 10 off ebay.
it has the following already done to it:
Upgrades
Metal gear servos, front and rear
Wing delete kit- relocates top links to a stronger center point. Looks much better
Hardened drive pins, not installed.
Outcry dual motor ESC $60 value- ESC has an external BEC on it, and also has a cooling fan. Traxxas plug is installed on esc and batteries -
2 spare upgraded motors. I bought these to install if the stock ones ever died, but they are still running strong. 4 working motors total
Spare higher capacity batter
Front shocks are upgraded and fully adjustable
Front links are bent derlin links
Battery tray modified to be lighter
Body trimmed and lowered
Panther tires on beadlock rims - stock tires and rims included as well

i got it for $150 shipped. i know thats what they cost new, but i figured with all the upgrades it was worth it.
but are there any other mods that are common for the RS 10?

oh, i also notice in alot of threads i found on the rs10 that many have locked-out the rear steering.
WHY???
i think that the 4ws is one of the coolest features!

Sounds like you got a ton of extras!!
They lock the rear steer out for competition crawling. (not legal)
I have a cliff climber and ive kept the rear steer because I like to watch it crawl
using 4 wheel steer. (even thou its sloppy sometimes)

this was the sellers pic
i have a lexan truck body that i hope can fit good.

look around your local thrift stores, I got a tyco or new bright truck
with a ford 4 trax body I mounted on my CC , looked pretty good
I may have a pic.

that looks WAY nicer than the stock body. its kinda sad, the stock body. redcat did a really good job designing this crawler, and put it out at a good price point....but then gave it a ugly body(my opinion)
i bet if they had used a standard truck body it would have sold better. the stock body makes it look like a toy, like its not well-built.