I used to have many domains at NameCheap and left after their redesign a couple of years ago. Huge spacing, many clicks to get to any information, and good luck trying to update multiple domains. Seems like they wanted to alienate their pro/bulk users in favor of the buy-a-one-page-website crowd.

Route53 (using now) just makes more sense: easy programmatic access, unified billing with other services, included domain privacy, and no games with renewal pricing/discounts.