Hand vs. Kathy Liebert $2,000 MTT at Bellagio

This is a hand from an MTT at Bellagio that I just played in, and I think I misplayed it and would like some comments on it.

Blinds are 25/50, and I'm in the big blind with like 3,800 in chips. All the players are unknown to me apart from Kathy Liebert who I have seen playing on TV, but not played with myself before.

2 middle position limpers.
Kathy Liebert limps along from the button.
SB completes and I check in BB.
I have ATo

Flop: 3s9dTd

I lead for 200
Folds to Kathy who raises to 600. She has like 10k in chips.
SB folds.

Here I chosed to call, which I think was a bad play. I think this is a spot where I should have 3bet even though I only had top pair top kicker. Does 3 betting here make sense, why/why not?

I played next to this lady down in Atlantis. She was sitting directly on my left (with the orange, ldo). BIGGEST NIT EVER.

First impression is NO WAY do I want to 3-bet here. I probably call and try to play small ball from here on out. Given stack sizes and position I might just muck it.

Hehe, she had the orange now as well, she did not seem to play nitty though, but this is just 45 min into the first level so it was too early for me to say.

She has a set here 80% of the time. 2 pr the rest.

I call because she's a women....
yeah this deep i'd think you should fold here.

fold >>> push > call.

Re: Her nittiness, a week later than the above, she went bust in a 2k WSOP event with JT making only a pair while she still had plenty of chips. So she can mix up her play.

In the above hand, I think that she could reasonably have a draw as well as the previously mentioned set/2pr. She definitely has enough chips to make playing a draw fast correct.

That said, without any other reads, I don't think she has just a draw enough of the time to lose more chips here. Folding could be a small mistake. Calling/raising could be a big mistake. I fold.

What about raising PF to push out the limpers? You could have just had this hand PF with a 250 chip raise...and if you get a call, you probably are going in with the best hand, right? I don't play anywhere near this level, keeping that in mind Just curious