Crossovers are very tough to actually design....If you havent studdied them well.
The crossover point depends on the filter ORDER/type and along with that of the OTHER drivers.
Say you go with a ODD order butterworth filter for your tweeter's highpass, then you also go with the SAME for the midrange. For them to blend proper(flat) You must allow the F3 point of each driver to be the same because they will sum UP 3db at that point. If you choose an even order then they have to cross eachother at F6(6db down).
What's more is that even the acoustical phase of each blended driver will change the crossover! What i mean is the placement and angle of each component will change the crossover.
Also if you use inductors they will carry resistance...Maybe not a whole lot but be carefull. If it is significant then you will change the ts paramaters of the driver like the Qes which is something that is much more sensitive for high frequency speakers.
Its seems easy and you may want to try but you should study design first.