Are you applying as an international student or domestic?
If Domestic, you will be able to get a good CS job from U Houston, and many other non-reach schools. If International, staying in the US after you get your degree will be more difficult.
UIUC says discrete math is highly recommended. So, that means you should take it…without it you will be less competitive at all your reach schools. Can you fit it in next semester? Are all your other classes requirements/highly recommended too?