Based on what you've said & the fact that you're happy with your rhythm sound, here is the best advice I can give ya.
It's actually a fairly simple process for ya and can be fun & rewarding. The goal here is for you and your sound to stand out, be clear and articulate without standing out like a soar thumb or blowing the audience's eardrums out.
There are a few things you can do to achieve this. I'd like to note that it's also important to keep the same general tone to some degree unless that's something your trying to go for. The same general tone also keeps your frequencys sitting properly in the mix.
1. EQ: Give yourself a Mid & Mid-High Boost. The Frequencys ya wanna boost are going to be from 800-1000kHz & around 4000kHz. Between 800-1000 will give you fullness and really help you stand out without mud & around 4k will give ya sparkle & articulation without being piercing or 'ice-picking' listeners ears. *these are real good starting points for EQ and are not set in stone, you may have to go higher or lower depending on what you're starting with. Usually a boost of about +3dB should be enough with a modest Q if you're using a Parametric EQ.
2. Effects: Adding some subtle effects will also help ya stand out. I like a 1/4 note TAP Tempo Delay a lot of times. It helps smooth a lead out and gives it some space and richness. It's important to keep it subtle though, (not a lot of repeats, or level) just enough so it there but not apparent, using a tap will keep your repeats in time which, first off makes it seem like you know what you're doing, and will help keep it subtle and fat.
You can also add in a detune pitch shifter somewhere around 3-6 cents and 30-40% mix. That'll fatten ya up, add some spacial dimension without sounding too chorusy or washy. You can also achieve this with a chorus or a micro-delay, and they all have their own flavor while being very similar in how they sound. Kinda' like different flavors of Vanilla Ice Cream, they're all vanilla but they all taste a little different.
3. Drive/OD/Dist: If ya need Gain, well then ya can always add a stomper in before the amp. Personally, I always prefer to do a X/Y amp and get my gain from the amp, but that's just how I approach it. I still almost 100% of the time will add at least EQ to help it cut. I feel it's more natural sounding and usually sits better with getting a little extra volume from the eq boost than just an overall boost. Seems to me I'm not quite as loud, so it's easier on the ears but yet still stand out nicely. IMO, there's nothing worse than being too loud in the mix. Kinda' makes it look like, "Hey everybody, look at ME!!!" Ya wanna blow people away with your playing, not your volume
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Hope this helps ya a bit. Just remember, there is no right way or wrong way. I've seen guys do stuff that I thought before hand, "Oh, boy, this is gunna be rough, and to my suprise worked wonderfully, on the other hand, I've seen dudes walk into a local bar gig with a 20 thousand dollar rig and couldn't get a decent tone to save their life, let alone a deceent lead tone.
