If you want to end up at SWA or any other major, try to stay away from 91/135 flying. Like you I want to get a job with a good major airline.
In 2008, I was FO at RAH and after furlough chose not to take recall, instead I was already in left seat flying a Jetstream 32 for a 135 company. At that time 1000TPIC was important, so I thought I was chasing the right carrot. Fast forward a decade and in a job fair I heard from swa recruiter that regional FO is more attractive to them then turboprop guy with several thousand of TPIC 135. I chose wrong. They can choose whichever way they see fit - you can't, so regionals are safer bet. Also, think of it this way, in 121 you will build a network of connections that potentially will help you with your dream job. 91/135 you will also be building connections but they rarely lead to 121 majors. Just my humble .02. Good luck with your ratings and future employment.