If you’re going to use the pool anyway, then IMO it would be much better to do so with the CNAME records, than to just use the naked pool records. That way if something goes wrong, the problem can be managed.
Vendor zones are supposed to provide that safety valve in a way that can be managed by the pool project, but given how long it takes @ask to get around to issuing them, using your own CNAME records is a good interim workaround that both allows future migration to a vendor zone, and ensures that your clients can be redirected to other servers in the event of significant problems.
I don’t speak for the project, but from my perspective your solution is to be encouraged, not frowned upon - it provides useful gains, adds minimal risk, and is clearly acting responsibly with the use of pool resources. I appreciate your effort.