This is off-topic here as everyone's supposed to post what they hate and should probably do so without backtalk
but I can't resist noting that
Starship was intended as a juvenile that was rejected by Scribners (who published his first 12 juveniles), that
Podkayne was a belated juvenile four years after that (when the Scribners had come out annually) whose original ending was rejected by
that publisher, and that
Friday, while perhaps the closest of the late Heinleins to early Heinlein, was still late Heinlein, which many fans either rate below early Heinlein or actively dislike. In other words, that wasn't The Ultimate Heinlein Novel Pack. I'd recommend one of the first dozen juveniles such as
Starman Jones, along with something like
Double Star for a good early non-juvenile. But, at the same time, nobody has to read anything, of course, and giving him three tries ought to be more than enough, anyway, so I could certainly understand your having no interest in trying more. Just thought I'd mention it anyway.
As far as being on-topic, for me, it's pretty redundant. The critics and I are usually at odds, at least when either of us are really fired up about something.