ooh, spending other people's money! one of my favourite hobbies!

the 135L will do you good on aps-c for indoor low-light sports or really tight head-shots, if/when you go FF it's the perfect portrait lens and won't be too long.
the 100/2.8 macro L is a stop slower, but for macro capabilities it's hard to beat (especially handheld with the fancy-pants IS). the 100/2.8 macro non-L is just as sharp (give or take a smidge), but has no IS.
i've got the 100/2.0, it's a damn old lens but honestly, for the price, it's very nice. Consistently sharp, focusses well, and a stop faster than the 100 macros. If you don't do macros and don't want to try, consider this one too. (it can be had second-hand for $3-400, if you don't like it you can always sell it again for the same price).

I've also got the 70-300L on my 7D, and wouldn't consider selling it for the 70-200L + extender, it's just better as a hiking/outdoors/generic walkaround bird lens (for those of use who can't afford the $ or kg of the 300mm+ überwhites), and no messing around with changing in/out the t/c. But if you want to concentrate more on indoorsy low-light events where you need a zoomable length, then 70-200LISII wins hands-down. Mayube i'll sell my 70-300L for the 70-200LISII one day if I make the shift to indoorsy events, but for now my priorities lie outside.

so i'm recommending the 135L, unless you like macros, then the 100L is where it's at... (or the 100/2.0 if you can't afford either of them)