mentsch > Don’t marry that optional second wife and instead use your extra time and energy to learn.
If you have 2 boys and 2 (or maybe even one) girl, then you fulfilled minimal pru urvu by both B Hillel and Shammai. If you went thru Tanach and Daf Yomi, you fulfilled minimal learning requirement. Now, you can choose which mitzva you want to do b’hiddur according to your preferences.
You can also marry a seminary graduate and learn Halocha with her, and a Stern graduate as the 3rd wife and learn Gemora with her.