There's an upgrade tiller elbow kit available. The Tackle Shack has them for about $80. It was meant to solve the problem of bad tendon connectors that they used for awhile, but it should solve your problem too.

Waves do have hull plugs just below the pintles; they should be standard threads.

Dead-down-wind will be slow on a Wave, but may be better than beating hard with an unknown boat. Keep your weight forward and steer with your feet (or tie the sheet to the tiller to steer) for better speed.

Welcome to the club! Have fun with it!