Combination of 1st order and 2nd order crossover in 3 way box

I'm re-doing some old Sansui 3 way boxes.  Is it crazy to use a 2nd order crossover between the mids and highs but a 1st order between mids and lows.  I want to crossover at 375Hz and 3K Hz.  With the response of the mid and high drivers I think they would be better served with a steeper slope at the 3k mark.  Does anybody have a crossover designer to help me with this or am I going to cause more phasing problems that will negate the benefits?