I have danios in my 29, what should be next?

I would leave the PH alone....how high was it ?

You usually run into more problems messing around with the ph rather than just leaving it and allowing the fish to adjust.

How long has the tank been up and running ? Have you read the sticky on cycling a tank ? If you have...and the tank has been running long enough to have completed it's cycle...you can add a few fish, wait a week or two and add a few more....keeping an eye on parameters between each addition so that you can tell when the tank has adjusted to the new load.

Betta and gouramis may not get along at all...so I would go with one or the other if you want either one of those.....

guppies and bettas sometimes may not go well as the betta can somtimes mistake guppies for another male betta so I hear.

Cories are always a good option in my world...lol...you may also want to consider kuhlii loach as well.

A pair of blue rams will do well in your tank...be sure they are a bonded pair though. They usually get along with just about anybody from my experience....except....sometimes corys. Some people have problems mixing corys and rams, some people don't.

I'm pretty new to this hobby, so I can't speak from experience, but I can relay what I've read during the course of my limited research for my own tank. As far as I can tell, using chemicals to adjust ph is actually worse than just leaving slightly high ph alone and letting the fish adapt. It's my understanding that ph reducers or increasers will create a yo-yo effect causing swings in your ph, which can be worse for your fish then just having them adjust to water that is slightly less than ideal.

As for stocking, I'm kind of going to same route you are with my 29. I'm planning on gouramies, peaceful barbs and some tetras. I'd love to get some blue rams myself, but have read that these can be very sensitive, so I was going to wait until my tank was well established to get a pair, if I do at all. My favorite gourami is the Pearl gourami, these fish, when in full color, are some of the most beautiful freshwater fish imho. A quick google image search will show you what these look like if you're unfamiliar with them, and I've found them to be fairly common at the fish stores I've browsed through.

One other word of caution, I've read that combining a betta with gouramies or guppies is not a good idea because they are too similar, which will cause agression in the betta. I'm not sure on the compatibility of guppies and gouramies.

Again, I'm just a newbie, so take what I say with a grain of salt. I just thought I'd chime in with what I've learned so far. I'm sure some more experienced members can give you better details and info based on their own experiences.

also keep this in mind about the ph

even if you can get it right you have to try again every tiome you do a waterchange

if your fish adapt, your tapwaters almost allways the same

Fish are best with a stable envoirnment over a specific envornment. If your tap water has a high pH leave it alone. Unless your water's pH is over 8 it shouldn't be an issue. Adding a ph lowering thing will work for a while, but the pH will start to rise again. The onlything I add to my tank is decholorinator and a buffer that matches my tap waters pH.

Could try dwarf gouramie

I'd think a dwarf gourami and a pair of rams would be really nice. I really like guppies because they breed like crazy and the fry are great food for the other fish.

What you are thinking of is very similar to what I want in my 46G.