That's only three maps. There are over 70 official Valve maps. I bet most of them went through massive changes. And what you don't see is the practice and failed attempts that helped to form the final, finished product. If a map is good at a1 it's probably because the author knew what he was doing, did a lot of planning and private testing, or just got lucky. Either that or people decided they were good, maybe because they were different to what they already knew.
If you take your experiences and make new a1 maps in future, each one will be better than the last attempt. No one is born with 'the knowledge' of 'what makes a good map'. It's all subjective to each person's preferences, and half of general consensus is likely to be popular opinion, based on existing works.
Your map has been improved because of the changes you have made, but there still seem to be problems. Some of them are probably side effects of improvements you made to other areas. If you continue to solve problems when they appear, eventually you will reach an acceptable map. You will only see these problem with more play testing. Try not to overfix problems. Make careful changes that are backed up by solid reasoning.