I've played it and put something like 10 hours into it or more just because. I do think it has incredibly fun gameplay, but as silly as it may seem, the story is a huge part of Metal Gear for me. There isn't much there in terms of the story, and that's what I mean in terms of the scope being like the Tanker section.
And no, the insertion points and everything don't really make Omega base feel like a different place every time for me. There is night and day, those feel kind of different. Same layout, but visually there is enough of a difference. Maybe it has to do with the order I did the missions in, I don't know. But I saw the entire base pretty much in the ground zeroes mission, and I saw the entire base in the mission I chose to do after that. Soldiers have a different routine in each mission and your objective is different, and this adds good variety. The base doesn't feel like a different place, though. I can use the same strategies in every mission in pretty much the same spots to reach my goals. I'll give you that it feels like a different place after going from night and stormy to a clear, sunny day; but I just can't understand the thought that it seems like a different place after that. I think more weather variety might have helped. The Deja Vu mission on the PS4 version has snow (though I can't remember if this is only when you have the MGS1 skins on after completing the mission the first time). Had the ground been snowy as well, there would be added effect of being able to be tracked by your footprints and stuff which would have been nice. Having it be foggy could have made everything feel pretty differently just because your approach would need to be different.
Those are just my thoughts. But we can have differing opinions and I'm glad it was worth the price for you because it sucks buying something and not feeling like it was worth it afterwards.