Based on what I've seen, it seems like, after Battle Fever, when the Sentai franchise was officially created, they tried to avoid big colorful characters for a long time, while, in Rider, you had heroes like Stronger and Amazon and a side-kick like Gan Gan G - even something like Hongo's cyborg angst is something you wouldn't see from a Sentai character at the time in any consistent basis (outside of episodic plots).
Aside from that, there's the villain structure - Rider stuck with a single active commander format for a long time, using a few unique structures once in a while (like the episodes where Shinigami returns in the original show, two commanders in Stronger's first half and also Stronger's second half, where every enemy was a commander) only changing to the standard multiple commanders format with the second half of Super-1, while Sentai jumped on the idea of multiple commanders around at once interacting with each other constantly as soon as it was 'officially' created.
There's also the obvious difference that Rider had crossovers between different shows in the series themselves and in the movies, while "official" Sentai was completely standalone (With the only crossover being Goranger Vs JAKQ, two series which weren't considered Super Sentai at the time) and even the Space Xeriffs, although also in a single continuity, generally avoided proper crossovers.
Regarding the Rider-specific elements and themes, I don't think they really appeared significantly in Sentai or Space Xeriff, aside from the mode of operation of the early evil organizations. You could see them in some other Ishinomori shows though.
As far as technical aspects go:
-Before Skyrider, Rider seemed to avoid ending every battle with the same finisher attacks every time - even Skyrider itself mixes things up later though thanks to all the past Riders popping up.
-Early to mid 70s Toei toku shows didn't seem to have green screen techniques.
-The action becomes faster in the late 70s and early 80s.
-In the 80s, they started favoring shooting in a few specific locations, including that infamous grayish rocky area that Toei reused up to the 90s. In 80s shows, you could often see heroes jumping from anywhere in the world and ending up there for their battles.
