Can't say on the controller board, but as far as charging, the limit on high drain batteries is typcially 2C which is two times the charge. So for the Sony VTC5, you could charge one with with two times 2500mAh or 5A. Though, you'd have to verify that with a data sheet. Might be 4 Amps or something.
I believe the Samsung batteries you mentioned are standard Li-Ions which are limited to a 1C charging rate. So for those, you would not be able to charge faster than one times the capacity which I believe is 2A.
Keep in mind you maximize wear when you charge batteries at their maximal rate.
You're going to be limited with a USB charger to a 1A rate. As it is, 1A pushes the connector to it's limit and also the linear type regulator chip typically used for those. You can find very inexpensive 1A USB chargers around. They've been discussed on the forum here. There's one from China you can get for like a dollar a pop. Can't say on the quality, but haven't heard anything negative yet.
If you want to go higher than 1A, you'll be getting into a non-USB configuration. For that, I would just use a hobby charger with an accessible plug for it in the mod. Otherwise, you can remove your cells and use a round cell charger with a higher rate, though it's hard to find them over 1A.
