I've done similarly with an acquaintance from the club

First was to have him handle my standard A2 rifle. Next a flattop. We went over the basics... kinda of a AR 101. Next step was to go down to Sportsman's Warehouse where they got a ton of ARs in most configurations to handle. Even though his AR knowledge was pretty thin, having just a bit of information under his belt allowed him to ask the sales guy some real good questions while I kept my mouth shut (I hate it when someone tries to barge into a conversation between a salesman and customer at a gun counter).

Anyway... he ended up selecting the equivalent of a S&W 15T. I think that was a good choice for him and generally in line with the scenario offered in the OP.

Generally speaking, I think a free float handguard and folding sights is a good general base configuration for those who are new to the AR world.