My pleasure.
You can do better than "ok" with one strobe. There's no reason why with the right techniques and the right subjects you can't get cracking images. Two strobes gives you more options - not necessarily better than "ok" pics 
Other than the Z330, I can really recommend the new Retras - the Pro and the Prime. Bit more expensive than the Z330 but a terrific strobe. I've just moved from Z240s to the slightly cheaper, slight less powerful Primes and am delighted with them. Apart from great capability and exellent build quality, they are are truly design art! The support from Oskar (who is often posting here) and the company is first rate. There are several reviews of the Retras if you search around WP.
I can heartily recommend the Inons or the Retras. Both would be a good "investment" (ha!) which would grow with any system upgrades that you may make - unlike the majority of the gear we all buy (housings, camera bodies). And starting with one of either would be just fine.
I'd also suggest pairing either with ULCS arms. Really long, hard-wearing and one of few other things that grow with you. I've had mine 20+ years and pretty much good as new.