Just wanted to chime in to recommend the program at the University of Houston. My experience as a student has been overwhelmingly positive. This year so far we have first-round offers from Northwestern, Michigan, UCSD, UCR, and Ohio State. High wait-listers at Cornell, UNC, and Arizona. I'm happy to answer questions about working with particular faculty and the like.
Deadline info is below.
Applications for Teaching Assistantships may be accepted as late as April 1, 2020, but for full consideration, the deadline is March 1, 2020. (It can take some time to process transcripts, both at the sending and receiving ends, so it is wise to send in your application well before the deadline. For further information, contact the director of graduate admissions.)
Applicants who do not wish to be considered for a teaching assistantship may submit completed applications as late as May 1, 2020. However after April 15, the department will close applications as soon as the class entering in Fall 2020 is full. Therefore, it is to your advantage to apply as soon as possible.