I'm developing a device to measure: light, temperature, humidity, sound and air-quality. The sensor choice is almost complete. But I have problems to decide how I'm going to take the measures. First, I though of using a servo to take different values, but now I'm thinking of using a portable device such as a lux meter, but with all the sensors.
The arduino takes 0v-5v analog input, digital hi/lo input, and some communication interfaces such as serial TTL. Are your sensors capable of supplying data to the arduino in these formats? Figuring this out would be a place to start your project. Not sure where a servo would fit in.