Since you phrased it "try something
new" (rather than "get a higher mAh battery for this 510 atty"), there are other directions you could take as well. The eGO (or its clones) will give your PV a new nifty look and many more puffs per battery charge, but the experience of the vape will be very similar. If that sounds good, follow Kent's great advice.
But if you would like a different vaping
experience (i.e., the feel of the vape), only a different
atomizer will give that to you. That difference could be just greater intensity, which can be accomplished by using an LR 510 atomizer on that eGO. Some flavors (and thicker e-liquids) need those extra watts of power to really blossom ... and the vapor and TH will be dramatically increased when using any e-liquid.
A different model atomizer also will feel different. You could experiment inexpensively by buying a Joye 306 atomizer and using it on your current 510 batts or most other atomizers and their corresponding
$2.50 adapter for use on your batts. If you like it, you could spring for the full kit.
My base of operations is the 901/Kr8, i.e., Kr8 batteries and 901 mod fittings (same threading) for use with Kr8 cartomizers and 901 atomizers (no adapter needed) ...
and penstyle and 510 atomizers with adapters. [Because of
adapter availability, your 510 might be the more convenient base for using the 401 and 4081 atomizers, which I've not tried.]
The Kr8 battery is the most powerful (in voltage and mAh) of the skinny batts. And the 901 is one of the two most common fittings for mods. These days, I've been enjoying using all of those atomizers/cartomizers: each providing a different experience, but only one mod or skinny batt needed to use them all.