I think the sucess of Amazons really reminded Toei that the vat majority of us KR fans are older and that we need depth to a shw to enjoy it. They're also noticing how children are able to appreciate three-dimensional characters and the way this leads to family dicussions. Yeah, it's about selling toys, but at the same time, Kamen Rider spans what... three generations now? four? and Toei needs to be able to appeal to all of those generations of fans if they don't want this franchise to crumble.
One thing that fascinates me is that the Bugster seem very one-dimensional on the surface, but we're learning that there's more to them through little hints. Both M/Emu and Parado are obsessed with "the game", which is something native to their base programming. Yet we see Parado being motivated in ways you wouldn't expect. He doen't kill a defeated enemy, he forces them to become stronger. He switches sides when someone's interrupting his game to maintain balance, yet his interest in Ex-Aid seems to be more of a competative comeraderie than a rivalry.
My prediction for the second half:
Spoiler
We know that Kamen Rider Chronicle is supposed to turn the whole world into one big game. I can honestly see this turning out similar to KS7, with Parado joining the doctors against a new viral threat which may destroy both human and Bugster.
Another good possibility:
Spoiler
The show turns to the excellent "multiple faction" formula that shone with the Orphonok in Faiz and resurfaced in Amazons. This didn't wok well in Ghost because of the shoddy writing, but I could see great success if M/Emu begins working on a vaccine that allows humans and Bugster to coxist. We've seen it's possible through not only the M/Emu internal symbiosis, but also as an external symbiosis with one of the patients in a recent ep. Which side Parado takes in this is unknown, but it is entirely possible he will find being human to be a game in and of itself. However, Chronicle promises to amp things up by infecting the world withthe Bugster virus, so I'm seeing a new baddie that replaces our current Gamemaster and is intent on destroying humanity (again making Parado choose sides, since this would mean an end to the game). Kamen Rider is full of villains who change sides to protect their personal idealogies, and Parado strikes me as more of this type than a loose-cannon.