Fast arduino microncontroller for flight controller

So guys, I am programming an arduino based flight controller. I have it working properly, both the stabilized flight and the rate mode, but now i want to add gps + barometer. I am getting gyro and accelerometer values from the mpu6050 dmp. My already working code runs at approximately 270hz (i used a function to count the amount of time loop() was called in a second), but when I add the I2C code for the bmp180 (barometer) it drops down significantly to ~25hz. This is ridiculous, and I havent even started reading the rx pin for the gps yet. So I wanted to know if u guys can recommend a microcontroller that is at least 70mhz and has more flash than 32k (if its not Arduino based pls include some docummentation to learn the new api)

I would look closely at the BMP180 Datasheet especially page 7 which gives you data on conversion times for pressure measurements based upon the resolution it is set up to read. When using the highest resolution mode the conversion time of the BMP180 can be as high as 76.5 ms which would lower your update rate. So check your initialization code for the BMP180 to see what the resolution is, if the conversion time of any sensor is slowing the update rate a faster MCU won't fix the problem.

Look at the Teensy 3.1 if the conversion time of the sensor is not the problem, you can program it with the Arduino IDE.

So if i try to read the bmp value before the 76.5ms the program will stall until that times is reaches?

Need to see your code. Like wwbrown mentioned you can't get it to output new values any faster than it's capable of, but that doesn't mean your program needs to sit on its hands and wait for the sensor to complete a measurement. It's possible to tell the BMP180 to start measuring then you can do whatever you want in your code, come back later and read the measurement.