Drawing districts should be done by non-partisan committees created by nominations by both major parties.
As it is, the majority party currently is allowed to draw districts specifically designed to dilute the voting power of the opposition party and even minorities.
Here is a map of the Houston area. If you look closely, you will see that the inner city of Houston is divided up into several congressional districts. Each district takes a portion of urban Houston and then incorporates a large portion of suburban and rural Texas. You will notice that it sort of resembles a flower with each petal beginning near the center and spreading out into the rural landscape. The net effect of this is to make each district a white middle class majority. People of color and poor urban whites are not equitably represented in any district. Consequently, even though Texas is over 50% registered Democrats, Republicans control 24 of 36 congressional districts.
Further, of those 24 red districts, 23 of them have representatives that are white men. Not a single Hispanic or African American among them. The remaining red district has a white woman.