I love Textra, but since they just won't implement texting from a computer (they've categorically, and a couple times quite rudely, stated that they're not interested in ever implementing that and you can use crappy relay services like Pushbullet or MightyText). So because of that I was forced to switch. IMHO Google's Messenger is just awful; too plain for my taste. Therefore, my 'weapon of choice' is now Pulse. It's nearly as good as Textra (missing a couple items, but good for the most part) and for 10 bucks you can get the lifetime license to do texting over pretty much any device out there and also from a web browser, so they win on that front. Not sure if they integrate with Android Auto, but since they are still one of the few with an ACTUAL app for Android Wear 2, I don't see why not. (The app is free if you don't need the cross-platform/web sync feature)