Something to satisfy my itch for a sporty car, but with good reliability and reasonable price point

You should be able to find lightly used BMW 3-series for this price point. The Audi A4 and Lexus IS-F that you mentioned would also be solid options. If you can find a certified pre-owned version of one of these, it will help your piece of mind, given the potential cost of maintenance. Infiniti sedans in this price point should also be considered.

If you don't care about brand and like the S3, you should consider a lightly used VW Golf R. It has the same terrific drivetrain as the S3 and is less expensive. You can find them with very low miles for around $30k. Interior quality and features is on par with the luxury brands. Look for one 2004 and newer for the new body style and excellent MQB platform.

I would also suggest the VW GTI which is, IMHO, the hot hatch for adults. My golf instructor, who is very much into cars, just bought a GTI and is very impressed with it. I'd also suggest a lightly used BMW M235i.

I drive a GTI and was going to suggest it as well in my post, but I suggest it far too often..... I actually was considering a used 3 series wagon but chose the GTI because it had more room, cheaper service, better performance (compared to 328) and gets better mileage. The R gets you AWD and a touch more class, but isn't really any more fun than the GTI and the interior is mostly the same. A loaded GTI Autobahn or SE is a pretty nice place to be. The 2018 gets a new digital dashboard that is similar to what Audi uses and is a nice upgrade.