plus let me fuck her mouth aggressively; any ideas? I'm in Chicago but travel often.

Just read the reviews of the ladies in the areas you are visiting.

She'll need to know in advance, but it can probably be worked out.  She'd hate to answer the door and find the postman there with a package that needed a signature receipt.

The second part... you can check reviews, and also discuss it beforehand a little, but she's going to need to know that your definition of "acceptably aggressive" and her definition match up well.  That's difficult to figure out by email, and may require an initial visit to establish some ground rules, and a comfort level with you.  There's also the question of physical compatibility; her answer is likely to be different if you've got a 3.5" cock from her answer if your cock is 13.5".

For that matter, she may not feel comfortable discussing anything of a sexual nature until she's seen you for an appointment already.  You can often get more elaborate requests fulfilled if you've built up a rapport over time.  You'd be amazed at the weird shit some people come up with.