I had the 737 Type and during my CAL interview, they asked me about it. As long as you can handle yourself, having the type rating won't matter. Every time you fly, you have an alternate airport available. Same thing for career planning - there's nothing wrong with having a backup.

Having said that, as good a deal as a $3500 type rating is, I really don't see SWA hiring in the next 1-2 years. Maybe I'll be wrong.