There was a time when nobody had any AA and did just fine, and they didnt even have gear from 3 or 4 expansions ahead of the content they were fighting, so I dont see it as being a big issue. If your having fun, and are not a liability to your groupmates, then go for it.
It will be interesting how you do in MPG and beyhond as there is a bit of a jump in the power of mobs there compared to WoS. Also getting into newer expansions, they scale mobs to assume characters have a certain number of basic AA's ie, hp, avoidance and mitigation wise.
Imho AA's have always made things easier or more fun, least utility wise, but levels and current gear is what made things possible. Today most groups are spoiled, in that survinging isnt enough, they want to slaughter mobs quickly with little or no risk or downtime. I personally like the quicker pace of a good grp, but most of the time my group of friends is pushing the limits of what we can do as we dont have a cleric or warrior tank. Often people are afraid to join us or dont believe we are successfull. But we have been, and have had fun doing so.
Enjoy!