If Shadow was curious and surprised enough to know why he was sent to specific locations Sonic will travel to in his later adventures, he would've been slightly interested to learn where he would go later. But, knowing Shadow's own nature, he doesn't have time to sight-see later locations or anything Sonic would do. He's only around to find and settle matters with Black Doom, nothing more.
And, whatever memory of future locations Shadow visited will pretty much be wiped away the moment he finishes off that vile intergalactic conqueror and leaves White Space when Sonic defeats Time Eater. Better off he doesn't know about them yet. Trust me on that.
What I'm kinda feeling a bit curious, though, is that most of each stage's Acts were kinda a bit shorter, compared to select past games' stages, and that Classic Sonic's speed was kinda too fast when using Spin Dash, compared to the proper speed in past games. Act 1 in many stages, aside from Plant Wisp, did feel they were over with far too soon than I previously thought.
City Escape's chase with the G.U.N. truck was a bit longer than the original chase from Sonic Adventure 2, yes, but the length was quite shorter, too.
Well, Sonic Forces' stages were underwhelmingly shorter than Unleashed and Generations' stages, too, don't get me wrong, but that was because the focus and time spent at that time was having the updated Hedgehog Engine 2 ready for later games; comparably, about 3 years of work, and 1 year of dev time it took for Forces to be made, aside from its rather slow pre-production work time alongside those spent years. It and the story was rather undercooked, too, proverbially, but that's not the point.
Shadow Generations' stages, other than the 2D and 3D perspectives being flipped, do have more or less their lengths being matched from others'. I would not think of any stage in it being a bit more longer than any of Sonic's past game's 3D stages, even when it runs on Hedgehog Engine 2, compared to Generations' use of its Hedgehog Engine.
On a more comparable note, regardless of version and platform, didn't any of you feel how shorter and different Rooftop Run's Act 2, for Modern Sonic, is, compared to how it originally was from Sonic Unleashed in Act 1, in Daytime Spagonia?
What I do remember is that stage taking reasonably long because of how good it is to see great fast speed across many sections involving using Boost, Quick Step, and Drift. That was so good! I can only guess the level's layouts between Unleashed and Generations were designed differently.
The more memorable setpiece from Rooftop Run was climbing up to the tall clock tower and grinding all the way down and forward, and I felt that in Generations, the tower seemed to be taller, yet the grinding speed was a bit faster compared to Unleashed, as if nearly approaching the ground from the top was faster than before.
I would think the actual stage length was cut down greatly for other additional side content and such to accommodate the anniversary aesthetics about celebrating Sonic's adventures.
Well, given the 360 & PS3's hardware's specs were slightly behind across each other, numerous differences aside, and if they were given reasonable hardware upgrades to better improve their handling on their graphics and CPUs, and if the 360's game discs were that of HD-DVD's capacities for some more bigger games instead(imagine if we got that alongside better reliability chances as better suited console refreshes, too), it seems like it was justifiable.
Overall, Sonic Generations still remains a very fun game, and Shadow Generations couldn't be any more different.
For the true handheld counterpart, on the other hand, should we have a more powerful and new standalone dual-screen handheld system, I would kinda think Silver the Hedgehog would get his own standalone adventure, aptly called "Sonic X Silver Generations", and that new adventure bundled with the 3DS version of Generations would be "Silver Generations", showcasing Silver being thrown into another adventure, and running across different stages from Sonic's adventures, only those truly from the handheld games, like Scrambled Egg, Aqua Planet, Red Volcano, Cosmic Angel, Ice Paradise, Sunset Hill, even Huge Crisis and Pirates' Island, to stop a nearly-forgotten threat that attempts to ruin his future again, which is, of course, Eggman Nega, with particular friends of Sonic's(like Gemerl, Tikal, Commander Towers, and Marine) and brief enemies turned temporary allies(Chief Pachacamac and his soldiers) the Time Eater dragged in, but having no involvement in Nega's latest scheme, would aid Silver's efforts to save the future, and its story would closely weave in with Sonic's approaching battle with Silver for the Chaos Emerald he held.
Well, any story with loose plot threads have to be closely knitted up sooner or later. And, the 3DS version of Sonic Generations only has one stage that represented Sonic's original handheld adventures, and, honestly, its not fair for only having one stage from it while the rest of the stages are from Sonic's past home console games.
Silver, so far, has not received his own solo adventures. It wouldn't be fair for Silver not to have one, right?
It's not entirely impossible for that to happen, too, having that and Silver's own adventure with it. Well, we can only hope.