A positive musical experience within the beast of SXSW is directly related to your expectations. If you are realistic about your access, and willing to do the tiniest bit of research (reading this post is a great start), anyone can manage and enjoy the overwhelming array of available music.
One strategy, regardless of access level, is to find a solid sponsor/venue, go early, and stay put. For example, Paste Magazine has consistently presented a steady stream of talented artists at their annual daytime party. An easy way to see good music with little effort is to arrive before the first set, post up near the stage and/or bar, and settle in for the duration. Since venues give priority to badges and wristbands as capacity is reached, early arrival is necessary for “RSVP only” attendees. The more access you have, the later you can arrive.
Greater access (badges and wristbands), will give you more flexibility. You can come and go between venues from set to set with a greater likelihood of successful re-entry. However, do this at your own risk. Even with a platinum/music badge, once a venue is at capacity, no one else is allowed in. The British Music Embassy also has an excellent track record of consistent talent, but their venue almost always fills up early.
Venue is key when the entire city is competing for temporary stages and sound equipment, so the safest bet is a location that has regular sound built in. Two great examples of exceptional sound are Central Presbyterian and St. David’s. Both churches are located in the heart of downtown Austin, and obviously have need for sound engineering on a weekly basis. Their sound quality is extraordinary, and it is always amusing to see how artists react to playing in a “church setting.” Comedy is sure to be included with the stellar acoustics.
As for specific mid-level music recommendations (with a bit of work anyone should be able to gain access), some repeat SXSW acts that are absolutely worth seeing live are Lissie, Lucius, and Joseph – all females, all badass. If you’re a sucker for bands with male and female vocals (as I am), The National Parks, Clean Cut Kid, The Ballroom Thieves, and The Heirs are all worth looking up.