You asked what trees other than oak to plant. Too many questions to ask/answer here. A lot of trees will survive in a given location. In my opinion, it's just as better to select a tree that will thrive in that same place. Fit the species to the location. You will have fewer problems in the long run. Consider water needs/availability, soil type & pH, insect/disease/deer susceptibility, desired size/shape, cost, plant availability, etc.
Don't be scared to plant a 5 - 10 gallon tree & let it grow. They don't give the immediate visual impact as a larger plant but with care early on, it will catch up & pass a 2-4 inch caliper tree in no time. They cost a lot less to start with & are easier to replace if one dies.
This is a place to start
http://texastreeplanting.tamu.edu/ but a web search will direct you to very informative sites. Area native plant society chapters usually have an area "expert" or two that can give their two-cents worth if you ask.