Delay: I agree. If you delay, your AoO's do not reset until you decide to act.
Ready: You clearly need to act (thus take a turn) when you ready so your AoO refreshes immediately. This, of course, lengthens the time until your next reset (perhaps, but you need to take the readied action later) as your initiative will be "later" (it could be earlier in a round, but you are then not acting this combat round).
If people play games around the "Marker" for the begining of the round is a problem with the players not the rules. Min/Maxers and other problems people see as rules issues are actaully player issues to me.
Waving your hands and ignoring the issue does not make it go away. You can't go to everyone's table in the world and give an ethical lecture on gaming etiquette.

If a problem could be abused, it's best to discuss it and see if there's a way to eliminate or reduce the problem than to just ignore it and claim that anyone who abuses the problem is a "min/maxer", "powergamer", or some other inappropriate derogatory remark.
I don't see how a character who can change when they go and ready is more concrete than something that never changes the begining of the round.
We were talking about "weirdness." IMO, it's weirder that your AoO would reset or change based on some undefined moment in combat from the
character's perspective, i.e. the EOR marker. It's much more concrete if your AoO resets at your turn. Consider the delay example versus the following EOR example. In the delay example, the character intentionally extends how long until his next AoO. This may give him fewer AoO over the course of the combat but in no way can I see any powergaming. For the EOR example, however, a character without Combat Reflexes could easily take two attacks of opportunity in a row before he gets another turn. One definition for round is "a span of time from one round to the same initiative count in the next round." So, essentially this gives a character without combat reflexes two AoO's
in the same round. That should be against the rules.
I am not sure how it doubles the number of AofO on a surprise round. The surprise round is its own mini round to me.
Actually, I said surprise round+1st round. Assuming a character has combat reflexes and doesn't act in the surprise round, he can take (assuming enough actions provoke) his normal number of AoO in the surprise round and an equal number before he acts in the 1st round. Thus, he doubles the number of AoO before he even acts. Isn't that weird?
Finally, I leave you with this quote from the SRD: "For almost all purposes, there is no relevance to the end of a round or the beginning of a round."