Cult Classic: This series is generally considered to be vastly superior to Challenge of the GoBots, even though it's nowhere near as iconic or well-known in the US.
Ensemble Dark Horse: For Japan at least, Leina Stol; much of the show's promotional art features her heavily and the fact that she was the central focus of the OVAs that continued the story pretty much solidifies this. Leina also gets plenty of fanart on Pixiv and the sudden death of her voice actress, Yuko Mizutani in 2016 drove this home even further. The Discotek release of the complete series helped popularize Leina to some extent in the West, too.
First Installment Wins: Whenever people talk about Machine Robo, usually they're referring to Revenge of Cronos as it's the most fondly remembered (it's also the one which appeared in Super Robot Wars); Battle Hackers is only mentioned in comparison to it and not very positively, and the one positive thing people will say about 'Battle Hackers is the catchy theme song.
The OVAs were frequently considered inferior by the few who watched it in the west, primarily because of the shift in focus to Leina and the entire "turning into humans" gimmick. Nowadays however there is a pretty big group of fans who came there precisely because they love Leina.
An image of Crane Robo's robot mode had his crane arm being photoshopped and GIF'd into a dangling piece.
Most Wonderful Sound: Emissary From the Sky. When Rom Stoll tells you to stop and listen, whether you're a heartless villain, Big Bad with delusions of godhood, or a mindless automaton, you better damn well stop and listen!
From Machine Robo Rescue:
Toy Ship: Taiyoh and Rin. Unavoidable when they're all kids really, but these two were given the most focus in the show and basically confirmed at the end.