..it seems the atmega328p (razor IMU module) connects the imu stuff via i2c only, so you may use SPI for a few 12-16bit ADCs to measure the strain (you may use few free analog inputs on the 328p as well, 10bits resolution). When you rewrite the sw then you can send everything via a BT connected. So provided
a) you will get 16bit values from all your sensors,
b) the amount of data to be sent is 3x16+3x16+3x16+4x16=208bits, plus some overhead
c) you will go with 57kbit/sec (probably the maximum with the 8MHz razor clock)
d) then ~200 measurements per second to get via BT is doable (no math inside the atmega328's razor module)..
p.