[jhkaghjkga]

That's wrong. You can get more than 5 certs/domain: either you have to wait a week (it's 5 certs/domain/week), or you include multiple hostnames in a single certificate (up to 100 IIRC). The latter would allow 500 subdomains/week.

[0x0]

That's quite limiting if you are handling customer signups, and it still breaks SNI-less clients except for the first batch.