I don't see the problem. Normally in 99.99% of ops it's 1 CC per 50 seats. By definition you can have not more than 50 pax. If operating with a reduced crew it's not more than 50 pax. Just that they're a little more spread out. Crew have the ability to rearrange the cabin as they see fit to ensure they can all see the demo. I don't think it's liberal interpretation at all. In normal ops is 50 pax per CC (regs state seats) vs. 50 pax per CC when operating with a reduced crew. No?
You'll have both of doors 2 covered by one FA each. The purser covers both door 1L and 1R. Almost exactly the same as 149 seater 737 that operate every day where two main doors are covered by one FA. So with having potentially one more pax I can't see safety being compromised in any way.