I would advise against those memory modules. That specific model number uses Hynix A-die memory chips. Ryzen tends to have issues with Hynix ICs in general, mostly with the M-die modules, but some of the other Hynix memory chips as well. Plus, it has a CAS 16 latency, and you will gain more performance out of Ryzen with low latency, high quality IC modules than you will with high frequency models alone. Those other modules I linked you to are CAS 14 latency at the same speed, which means they'll have a much lower OVERALL latency.
I realize you want the RGB factor, but in this case, with how fickle Ryzen can be when it comes to memory, I'd strongly suggest against it unless you can find an RBG G.Skill model that incorporates a Samsung B die IC and a CAS 14 latency. It will be worth the extra investment, if there is one, in terms of overall performance.
I'm working three other threads right now where we are trying to get these guys memory to work at speeds over 2133mhz. All of them are G.Skill and Corsair modules using Hynix memory chips. These are not limited cases. There are a ton of them on all the forums. BIOS updates have not cured all of the memory compatibility issues on Ryzen, only reduced them. There are still modules Ryzen simply does not play nice with.
These would be the modules I'd probably recommend, if you have to have RGB. Of course, what you do is entirely up to you, I can only offer you my opinion based on many instances of working with other members on memory compatibility on Ryzen builds. There are absolutely some instances of people having success using modules that others have not typically had success with on Ryzen.
Going up to 750w isn't a bad idea at all. In fact, I'd highly recommend it. Not only does it give you some headroom for overclocking, it also gives you headroom period, which means the PSU will likely be operating in a lower percentile of it's maximum capabilities and should have lower levels of ripple and electrical noise, better voltage regulation and will operate in a cooler thermal envelope which will also help it to have better longevity overall.
Considering that you'll be overclocking, you want a unit with mythic levels of those same values I just mentioned. I'd look to the Seasonic Prime series or a higher tiered Corsair model like the RM or AX models. The TX models are good, but they are not great, and overclocking is particularly sensitive to variations in ripple or voltage regulation. You want a unit with very little deviation in either of those. The Seasonic Prime series and the Corsair RMx, HX and AX units are what you probably ought to take a look at. When in doubt, find a professional review either here at Tom's Hardware or at www.jonnyguru.com. HardOCP and TechpowerUP are good sources as well. Oklahoma Wolf and Aris Mpitziopoulos are the two primary reviewers you want to find reviews from. They are far and away more trustworthy when it comes to reviews, and they have the best equipment and experience to make valid judgements as to the worthiness of any potential PSU purchase.