It honestly doesn't bother me that much; the great level design (with its secrets and alternate paths), mechanics and art style are more than enough compensation to me.
SS is not on par with PC (or Star Fox) in terms of level design and mechanics but still a very good game. Never got far in the Batman games.
SoulStar isn't just a rail shooter, remember. It's a good rail shooter, but it's a free-roam shooter as well -- and considering that the free-roam levels are the harder ones, it's likely that they'll be taking up more of your time, too. SoulStar's rail shooter levels are great fun, though, while the freeroam levels, and the bosses, all of which are fought in freeroam arenas, can be very frustrating... still, it's a great game, and definitely is better than SNES Star Fox.
On that note, I'm fine with N64 framerates, and think that they are entirely playable, and 32X 3d mostly is too (a few games, such as Star Wars Arcade in the trench/SSD levels, have drops that go too low, but otherwise it's fine), but a lot of SNES Super FX 3d games (such as below), Genesis 3d games (Hard Drivin' and the like...), or those scaler Genesis games I mentioned like Outrun, Space Harrier II, Super Hang-On, Super Thunder Blade, and such? For the low framerates in those first groups, or the horrible choppyness which is a framerate issue mostly but also is partially an issue of questionable software scaling... those I just can't take. They just run too badly to be fun. Star Fox 64 is my favorite rail shooter ever, but the SNES game? Between the awful framerate and the near game-killing flaw that they failed to include an onscreeen targeting cursor (so you have to shoot in order to know where you're aiming, which is very annoying), I don't like it much. Vortex and Stunt Race FX are no better. Choppy, slow, no fun. I actually do kind of like Dirt Trax FX, and like SNES Doom, though, so it's not all of them... but I think those two run faster than the other three.
I know this is a matter of opinion, though. A lot of people hate anything below 60fps, these days, it seems... but everyone has some limit where games stop being fun, yes? I don't care too much if a game is 30fps or 60 and often can't tell much of a difference, but I can definitely tell the difference between 5 or 10 fps and 20 or 30.
So yeah, 32X Space Harrier is absolutely amazing, but I'm not sure if I've even played Space Harrier II for the Genesis more than a couple of times, even though it was one of the first Genesis games I bought after getting the system. On the other hand, RoadBlasters, Burning Force, and Outrun 2019 show that it IS possible to do well-playing "scaler-style" games on the Genesis. Panorama Cotton, whether because of the ambition of the game (the amount of stuff they're putting on screen) or the tech, is not at that level of smoothness. It IS playable, I guess, maybe more so than Space Harrier II or Super Thunder Blade (and it certainly looks a lot better), but I just don't like how choppy it runs.
Oh, as for the Batman games, they're railed driving/flying shooting games. Very, VERY hard, but quite good and lots of fun... though yeah, I rarely get too far either, thanks to the difficulty. I love them anyway.