There are no USB 3.0 Interfaces available yet that I'm aware of...
Your 3.0 ports should be backwards compatible with 2.0 devices...
Any USB 2.0 Interface will work...
If your devices are both USB then you can use a hub if you only
have 1 USB port on your laptop..
Need a little more info then you've provided..
If your Keyboard is strictly MIDI and your Mic requires 48v Phantom Power
and is Lo Z....
Then probably the MOST bang for your buck will be the Roland Quad Capture.
They sell for $269 but you can usually find a sale at Guitar Center or one of the big
retailers to get that price down...
Excellent unit for the price..has two VS Preamps and MIDI in and out...built in Compressiion
on the preamps and records up to 192 Khz Sample Rate...and the drivers have extremely
low latency...
Also the Focusrite 8i6 is a very good unit...$299, but always look for a sale...SAVE MONEY
to buy other goodies..LOL