There are lots of great options but I personally like to take modern responsives and convert them to fixed-axle to get the best of both worlds. I call them Postmodern Fixed-axles 
. The plasm makes an excellent fixed axle with a bearing blank. I used to make these by bricking a mr85 bearing with epoxy - but I have to say that my recommendation now is to get a ZGRT mr85 sized blank - the flat groove reduces pad rub.
That said, there are lots of great traditional options. If you can find a TMBR, those are my favourite wood yo-yos, otherwise Spinworthy and Gates yo-yos are also great. Colin Leland, who used to make TMBRs, is apparently collaborating with CLYW for an upcoming wood yo-yo release. I’ve heard good things about Ed Davidson and Dazzling Dave yo-yos but haven’t tried them yet.
Also, the newest iteration of the Duncan Butterflies are BOMB. They play really well, especially for the price. If you get a purple one from the Rainforest website, that will be one. Also any of the special edition ones that Duncan sells on their Beyond yo-yo site. My personal favourite is the glow in the dark one. 
Edit: This is a slightly old but still accurate guide that I wrote to help spot the newest Duncan butterfly in the wild.
That’s awesome that you are enjoying 0A so much. The kick flip came naturally to me as well but I know it can be trickier for some. It just goes to show that we orient better to some tricks vs. others. I found the varial much harder to learn and more rewarding when I finally nailed it. Other ones that I am still struggling with years later are Drew Tetz Heelflip and Ed’s treflip. I am finally getting Ed’s lunar varial down, but it’s been years in the making. 
This instagram account (contributed to by 4 great 0A legends) is a great resource for finding more tricks to work on. BANDALORES (@bandalores) • Instagram photos and videos