Interesting situation, but like Rob, probably not a situation I would allow my self to get into.
Calling from the blinds with AQo is probably a leak - much better to 3-bet and take the initiative for future streets. If you miss the flop, at least you can continue to represent strength on later streets and make it look believable - and there"s no guarantee that villain connects with the board, meaning you get to take it down through simple aggression.
Once you"ve flatted pre, floating out of position (twice) is another leak (imo). By taking the passive float line, you aren"t selling a tale of strength here, which makes it hard for you to win on the turn or river, unless you connect with the board. If he has anything at all, it"s now very unlikely that he"s going to fold on the river - all good if you connect, but means you can"t win the hand if you don"t...... so put simply, your floating here is fishing, rather than floating with the intention of taking the hand down later on.
His pot bet on the river could mean anything - either a monster that he hopes to get bigger value for; a marginal one pair hand that he now figures is good given your lack of aggression and which he is planning to call with if you suddenly show up with a river check/raise; or a complete bluff to exploit your lack of aggression.
A 3-bet pre, or even a donk lead on the flop, would have cost you about the same as calling min bets on flop and river, got you far more information, and avoided facing a difficult hero call on the river when you don"t have a clue where you are. It would also give you a much better image - the line of call, check/call, check/call, check/fold is so weak and very exploitable.
Aggro FTW