Well, you already know what I think about IBKR. I love 'em and wouldn't use anything else.
The account opening process is easy, and it's completely online. The platform's hard to get used to, but once you're used to it it feels totally natural.
You need to keep an eye on dividend withholding taxes, same as you would with any other American stock.
The monthly minimum is $10 to avoid the pro-rated $10 inactivity fee, and $30 to get free market data for that month.
They do allow option selling and shorting of single stocks - they've got pretty much the biggest stock loan inventory of any retail broker.
I've never tried managing orders using anything other than the usual IBKR interface, so I can't speak to that side of it.
Basically they're a bit hard to use at first, and the customer service is a bit perfunctory, but if you know what you're doing they're absolutely brilliant.