While I kind of love this game I'm on the verge between Yes and No to recommending, because it has a lot of pros, but even more cons. I'll admit that I never got into the previous games, and I don't have the time or nerves to try playing games from 2000 either, so my review is based on SEV alone.
-The research tree is massive and really allows a lot of decisions on what to prioritize, some of the ideas an concepts in there are great
-The stellar manipulation tech tree allows the player to change entire systems and even build sphere worlds which are pretty damn awesome
-The ship building system (even though the component placing is nearly irrelevant, as demonstrated by the AI frequently) is pretty damn cool and it makes it possible to build ships and bases for all kinds of tasks, from tiny to huge
-The UI is somewhat hard to understand, but once you understand it you can find everything quite easily, especially since the lists can be directly adjusted to search and display only certain objects
-The gameplay and mechanics are generally and okay and would be fun, if not for the cons...
-The AI is horrible to say the least. Up to the point that within a typical game I can build dreadnaughts which waste entire enemy systems on their own, which might be fun to see the first time, or the second time, but yeah... not all the times after that (modding it to death does help somewhat, but at least for my playing style it just never managed to cut it, and searching for mods for hours to get something to work which should work out of the box is no particularly great fun)
-And the AI is not just horrible, it's predictable, and don't ever expect the AI to use something like stellar manipulation at all
-The micromanagement has some cool things going for it, but it get's really tedious after having a certain amount of planets, because appropriate mass commands and the likes are just missing
-The turn processing just takes too damn long later in the game, and I'm talking many minutes on high-end machines...
-...which in turn makes multiplayer games that much more unattractive, I never found anyone to play with, and thanks to these loading times I wouldn't want to bother either
-The non-steam version was a ♥♥♥♥♥ to patch, and the support in general wasn't exactly outstanding
-The game is moddable and it is pretty much the only game I seriously tried to mod, just to find a few senseless hardcoded things just about in the one wrong place (stellar manipulation is rather strictly limited to what it already is)
-And all those cons add up to one problem: The game never felt like a game, only like a sandbox, which is fun for some hours but not more
At the end of the day, if it's on sale and you're fine with a sandbox or just plain love big tech trees for the sake of imagination and creativity, grab it. If you want a game to just install and play then you should really stay away from this one.
Nevertheless I'd love to see SE6 but I harshly assume that'll never happen.