I moved my domains (50) from namecheap to porkbun and cloudflare for these reasons:

* the price of a domain would change after placing it in my cart or purchasing it (the purchase would be refunded, but it was still frustrating.)

* WhoisGaurd renewal messages and "warnings"; I needed a registrar that provides whois privacy - without a fuss.

* namecheap's dashboard only shows 5 domains on the first page, and they are not sorted by soonest to expire.

* slowness experienced when using their website

* their competitors are cheaper

https://tld-list.com/ is pretty nice for comparing pricing.