Bimble, the point is that most of those missing or lacking features were either advertised or they actually are in the game, just at the bare minimum though.
There is a tech tree with a random factor thrown in: but it's small and linear, and the randomness idea goes to waste being underdeveloped. Galciv 2 had no randomness in its tech trees, yet they were huge and did offer the player a lot of choices on paths to follow (weapon wise, for instance, specializing on a certain weapon/defense class, or the good/evil/neutral alignment subtrees), paths that had quite the influence on how you then had to play the game.
There are 10 factions... in name, they could very well just have put in 2, there would be no real difference gameplay wise. In Galciv 2 too there weren't enormous differences between races, yet some of 'em had some very game changing "talents", and their units were flavoured with different looks/components.
There are features on the maps. There even are rivers, just not implemented in game. But you can't really interact with most of these features, what nowadays you usually can do one way or another in most games of this kind. And I'm telling this from a turtle player standpoint, one who hates most "terrain changing" functions 'cause I tend to spend hours to design stable maps for a sieging kind of games that are often destroyed by terraforming and that sort of things (what I hated in the otherwise still wonderful AOW Shadow Magic, or why I never use the Illians in CIV IV - FFH because their expanding snow
).
Also everything else I mentioned: it's there, showing the idea and the intention of working on that part of gameplay was there, yet it was not brought up to full fruitfulness.
There are wandering mobs: but of few types. There are quests: very few and very simple (entere here, go there, return here. Not even yes-no situations except for the master quest... how would that have looked better if, even if into the actual game things were left as they are, there actually were some old school text-based "adventures" like it was done for Space Rangers? Nothing new to script into the engine, just a guy having fun writing some text quests, with a bunch of paths and maybe some puzzle thrown in here and there: zero issues, zero headaches for programmers, just plain and simple fun content, that would really go well with the old school stile the game is presented into).
There are items: few and pretty much all the same. Events? Now that I'm thinking of it, apart from some spawning of mobs because of a random event, nothing else; Galciv had several interesting universe-wide events once in a while, some so serious to be even annoying (turtle player here, part 2
).
Tactical battles are there, but they are the most streamlined I ever seen. Even the not memorable Lords of Magic's (from which AOWII SM took a lot) tactical battles were less rudimentary: they actually were tactical. What's the point of putting in the engine for tactical battles when you just have to move a couple tiles and spamcast skills/spells which actually are all more or less the same, with few, very few, status effects? There are not even elemental resistances in a game called Elemental... 
These much older games had skills and spells meant for a reason, city sieges and land features that actually made a huge difference on the battlefield (for starter, they did appear in the battlefield since they were on the world map, ahem...
): for what has been done 'till now in Elemental's tactical battles, they could very well either keep a CIV like battle system, or a GalcivII one where battles where pretty much just some cinematic fun for viewers. At least one would not have to feel cheated by such an underdeveloped feature, that frustrates you by showing you that the potential was there, the idea was there... it was just left... there.
This is the very epitome of what one would define "unfinished". Unfinished because it was began and clearly not finished to a satisfying state (at least for several of us, when personal tastes come into play all the debate goes into smoke... that's also why I'm not mentioning the - for me - unimpressing graphics). There's a bare minimum one would today expect from this kind of 4x games, because of standards set up by previous cult games (which I don't believe Elemental reaches right now), plus there's what you feel is lacking because the game lets you sample it, taste it, but not really eat it, since there's not enough meat.
GalcivII, for instance (and to keep confronting Elemental with another Stardock game, that for a good reason hadn't to face this all but warm welcome both from reviewers and many players), had no RPG elements at all (apart from experience for units, and the early game oddity hunt to gather bonuses). Yet noone felt they were missing, because the game felt complete, self sufficient in what it aimed to accomplish. Elemental aimed to accomplish much more, and elements of this goal are under the eyes of everyone while playing: but that's what they are, elements, ideas, drafts; maybe they aimed at a too big of a goal, maybe they were a bit overexcited when advertising all the feature this game was meant to have (raising our expectations and making us drool just to feel twice the disappointment), and maybe they rushed it a bit too much when another month or so of polishing could have done wonders in transmuting a "this feels an unfinished and poorly wrapped up game" welcome into a "nice game... there could have been much more in, but that's what modders are for" one.
I didn't even think of multiplayer since I seldom play online especially this kind of long spanning games. You are probably quite right in pointing that too as a fault, but I don't really feel multiplayer implementation is an actual "part" of the game itself. It's relevant, and good multiplayer support deserves a nice plus when rating a game, of course, but the game itself is... well, the game itself
And anyway, it would have been impossible, viewing the state of Elemental, to release it with multiplayer already active: many people are crashing constantly, plus there's that nasty memory leak, I tremble at thinking what curses experiencing all these issues multiplied by the multiplayer environment would have stirred up 
Mind me, I still love Stardock (not everything always turns out as it should, it's life, and I know that when you develop your own creature, being it a software or a work of art, sometimes you lose perspective and are not always right at judging it ready for the public), and I'm sure I will soon love Elemental too. I have no troubles at saying I (like pretty much everyone nowadays, let's be honest) play a lot of games yet I buy very few, let's leave it at that. Stardock games are usually some of those very few. For all the reason we know we have to praise and respect this software house, that deserves our money. Yet when criticism (constructive of course) is deserved, that very same respect binds us to express it.