If I wanted to joke, I'd say that anything is more versatile than a RAT... but IMHO, most of the drive pedals aren't versatile: to some extent, they all have a defined and recognizable voice IME.
Among those that I've tried AND that I've kept (or kept in their stock form, unmodified), the most versatile IME is the Blackstar HT-Dual: the "isf" parametric mid EQ gives different voicings and the two channels cover a wide sonic landscape. The 300v powered tube in it makes a definitive difference in natural and dynamics... Now, the pots are frail and must be cleaned often if we don't want this pedal to produce no sound. :-/
I also appreciate a TS driving a Blues Driver, both with gain around 10 or 11 o'clock: it gives two flavors of crunch (one mid boosted and the other mid scooped) but once the two pedals switched on, it's able to recall the sound of a RAT, with less noise and without the temperamental whistling that a RAT can produce when pushed by some other FX's.
It's also possible to mod a RAT: I've changed once the caps in a RAT clone to make it a bit tighter... but it was still not "versatile".
Now, versatility is not necessarily an advantage: I remember a dude trying a HT-Dual and a OCD in a shop. I had told him that the HT-Dual would be able to mimic the OCD while the contrary wouldn't be true... but he has finally prefered the OCD because he hadn't found how to set the HT. :-/
The OCD is relatively versatile BTW (but not enough to have retained me to mod mine).
Sorry for the long boring post. Good luck in your quest!
Kool and all good replies, really am interested in your personal I-love-it-that's-on-my-fly-board-b/c_it's-my-Ms.-Versatility-pedal. Any kind, new or old, cheap or take a loan out, any genre, any use, but it's your keeper even if you just respect but don't currently own due to Guido past dues. Ones for consideration that'd might never be ID'd w/out your Love-It embossed response. Bring 'em!
I see a lot of folks here recommending all sorts of OD pedals, some excellent ones even, however if I understand it correctly the question is "what's more versatile than a ProCo Rat?" and my answer is; very little, and maybe NOTHING, especially considering the price.
I've had various RAT's over the years, an original early 80's Big Box, a reissue Big Box, few 80's & 90's smaller ones, plus I've had the chance to play a couple of recent Made In China ones and even though they all sound surprisingly slightly different (yet all unmistakably RAT's!) one thing they all had/have in common is versatility.
Let's face it, with Distortion at 9 o'clock it gives you a rather warm break up (John Scofield's setting) then you crank that at noon/2 o'clock and it becomes a raging Overdrive (i.e. Steve Stevens) after which it transforms into a fuzz(?) and a very good one too; so you've got a single pedal that can go from "edged of break up" to Overdrive to Fuzz and everything in between, and all these settings clean up very well by turning down the Volume control on the guitar, and I haven't even mentioned how interactive the Filter knob is with with the other two knobs; I mean, what more does one want from a single OD/Distortion pedal????????
After all those above mentioned RAT's I've owned I finally settled on an early 90's one, and admittedly it's not the only OD I use as, like every other guitarist on the planet, I enjoy 'flinging" with as many dirt boxes as I have the chance too(!) however if I have to bring something to a session, maybe only to do some overdub leads, I know that the RAT will give me everything I need in that department, regardless of the amp I'm given.
Here's the link where the late, wonderful Michael Casswell demonstrates how wide a range of sounds you can get from a RAT:
I'm gonna be "that guy" and say my King of tone is the pedal for me its extremely versatile. Maybe does t get face melting gain but I don't really play with that anyways, but it can be used either to goose an already pushed amp with great results and can even be used to get a great tone at bedroom volumes. Most pedals do one or the other, too me most tune screamers only sound good through pushed amps not at bedroom levels.
The Rat is cool if you want some fuzz in your tone but, the XTS Atomic Overdrive is the most versatile dirt pedal I've every used. The Filter control on the Rat is very effective but the Atomic Overdrive takes that up by around 100 notches.
Yeah, I know you guys have seen me post this video a bunch of times before but it is a very accurate representation of what you can expect from the pedal.
Simply no complexly amazing performance and pedal, the XTS Atomic Overdrive with demo by Pete Thorn.
I feel like I visited a place forgotten about, back in adequacy. That just blew me away, made me want practice in earnest for real! Like being shoved up against the wall in Jr high school by an older classmate, it totally got my attention.
I'll have check the other pedal recommendations after some recovery.