Disabling the axis spawn nearest to the radio would create a huge bottleneck on the ladder. I imagine it would only take 2-3 allied players to completely block any axis coming up the ladder and after that, axis have no chance to defend the objective or radio from either spawn available.
As for the flag, I agree it should be made a permanent spawn after a certain time. But I'm not sure if most of the sk would still be allowed as there technically is another exit available (towards the beach)? Of course permanent spawn means axis could no longer shoot right into the spawn so that's still something.