101Domain: I'm not a fan of their UI and branding; it's unattractive to me. The prices seem quite high compared to others, as I've noticed while searching for the cheapest registration/renewal options on tld-list.com.
123-reg: I don't have much to say about this one; I've never used it.
Alibaba Cloud: If you have common sense, you would avoid this one. Its background is sensitive, and it's likely that your registrant information is stored.
BlueHost: It's not a viable option for my hosting needs; it seems to offer high prices for low quality, nor is it an option for domains.
CloudFlare: So far, it's been pretty great. The only downside is that it only allows the use of their NS. I like the UI, but sometimes the button response can't keep up with my clicking speed. It feels safe and privacy-protected.
ConnectReseller.com: I don't have much to say about this one; I've never used it.
CosmoTown: I've registered many .com domains here when it was the cheapest option. It has all the basic functions required. However, it lacks DNSSEC, and you need to contact support to add it. The UI is quite poor; it looks like something from a template sharing platform, but it works fine.
DirectNic: I don't have much experience with this one, but the price is laughable: $17.17 for a .com domain, seriously? (Many registrars have similar prices, though, but why would I use it?)
Domain.com: The only appealing aspect is the domain name of the service itself.
Dotster: I don't have much to say about this one; I've never used it.
Dynadot: Good UI, but like Cloudflare, the buttons sometimes need to be clicked slowly. The support is good with medium response speed. It supports a wide variety of TLDs and has a medium-sized marketplace and auction. The brand was hard to remember at first.
Epik: I loved this one before. In my opinion, it doesn't care what you do and won't ban you or delete your assets based on who you are or what you do. Or, perhaps it's intentionally supporting certain parties – I'm not sure, as I haven't done in-depth research. But, it felt safe to put my domains there, as it suggested before: the "Swiss bank of the domain industry". However, after the masterbuck incident, I lost trust in it, even though I wasn't one of the victims. When I wanted to transfer all my domains out, they retained me by offering a free renewal for a year. I hope it can be great again, but it's tough.
Fabulous: I don't have much to say about this one; I've never used it.
Gandi: I like it. The support is professional and nice. The prices are acceptable, and the UI is nice with a fast API. The corporate plan is great; some domains require an extra fee to register, but you only pay once for the plan to register as many domains as you like within the plan period, and you can keep them without the plan. I just wish they also had Gandi.com.
Gname: I'm not very fond of it; it seems to be deeply cooperating with the mainland China platform JuMing.com, which has a bad reputation in China. The UI is okay, and the prices are acceptable. However, the background of the platform is sensitive and insecure for hosting sensitive domains.
GoDaddy: I used it at the very beginning of my interest in domain names. The prices are unreasonable, and the support is terrible. The support staff seem to lack domain knowledge. I found that my understanding of domains was better than theirs. They couldn't address my issues, and I had to fix them myself. It's great if you don't care about the prices of domains but want protection for brands. The UI is okay, but bugs are never fixed. Searching for some domains shows they can be registered, but you cannot check out!
Hexonet: Prices are 10-25% higher, in my experience. The requirements for a reseller account are low. They offer top-level API response and safety. There are many functions, including setting your own auth code for transfers, DoNotResolve, Update, Transfer Lock, etc. The UI is clean and well-documented.
HiChina: I don't have much to say about this one; I've never used it.
HostPapa: I don't have much to say about this one; I've never used it.
Hostinger: It's more of a hosting option.
Hover: I don't have much to say about this one; I've never used it.
InternetBs: The UI is terrible. It's popular for uncommon TLDs.
Ionos: I've only used it once for the $1 .com registration.
Joker.com: I don't have much to say about this one; I've never used it.
Moniker: I don't have much to say about this one; I've never used it.
Name.com: The UI is too simple, and the prices are a bit high.
NameBright: The UI is outdated, and the support is always offline.
Namecheap: The UI is okay, although it looks childish to me. It's not as cheap as its name suggests.
Namepal: I don't have much to say about this one; I've never used it.
NameSilo: The UI is old, and there's constant switching between the new and old panel.
NetworkSolutions: It feels trustworthy. It's an old but strong brand. Network Solutions, LLC is a domain name registrar with IANA Registrar ID: 2, while 1 is reserved. I put my brands here, although the renewal is a bit higher.
Onamae: I don't have much to say about this one; I've never used it.
OVH: Terrible! There's no refund for prohibited domains. For example, I registered something like gov.tld, and the registration didn't complete. There was no automatic refund; I had to create a ticket to ask for one, and they refused until I gave them a 1.0 rating on TrustPilot. The UI is hard to use.
Porkbun: I love it. There are many surprises on their website, which is quite attractive. The UI is simple. Domain management isn't very responsive; it takes a while to load for each domain. Support is fast.
Public Domain Registry: I don't have much to say about this one; I've never used it.
Reg.ru: I don't have much to say about this one; I've never used it.
Register.com: I don't have much to say about this one; I've never used it.
Sav.com: The .com registration price was the lowest for a period, which is why I used it. Now, the new login page is terrible; I always fail to log in if I don't allow tracking cookies in Edge. The UI is simple, and the prices are a bit low.
Spaceship: It was good for the .com promo for a period. But I had an unpleasant experience with them regarding abusing promotions. They use tracking techniques to monitor my actions, which scared me off when they tracked me down for abusing promotions.
Z.com: I don't have much to say about this one; I've never used it.
Overall, I think I'd vote for NetworkSolutions, Porkbun, Hexonet.net, Gandi.net, and Dynadot, any one of them.