masterminded:
You are wrong.
I don't mean that to be insulting or to rile you or anyone else. It is a simple statement of fact. You are wrong. You are not wrong for not liking Civ V. That speaks to preference, but the specifics are incorrect. In fact, you've already seen that cultural vics outside 5 cities is not only possible, but possibly the fastest way to win Cultural right now, but there are other specifics where you are wrong.
1. Onerous restrictions.
In fact, going unhappy in Civ V only penalizes you by stopping upward city growth empire-wide. It has no other effect. You can keep plopping down Settlers anywhere you want until you get past -10. It can be hard to dig yourself out of that hole, but the key point is to manage your resources so that you don't get into that hole to begin with.
Even when you're very unhappy, your science and gold come in unabated, so you can easily keep pace technologically, and you can buy your way out of the hole you created. There are ways and means.
2. Inconsistent mechanics.
Also untrue. I believe that I have used every unit in the Civ V line, and those usefully. I only except the Missile Cruiser, which comes too late, and the Nuke, because I don't like it. Contrast this to Civ IV where the late game was so set and badly designed that many late game units simply could be considered nonexistent.
Build times are a non-issue provided that you pay attention to growth and production. Stables is a bit of a bad example because it is a corner case of specific building boosting the specific production of specific units. It's a lot like the Civ IV Stable, actually, and barring Cavalry abuse, those were pretty marginal buildings, too.
If you have enough gold, you can simply buy the happiness and cash buildings required for growth, and be able to build units well. If you don't have enough gold, your cities should be having enough production to not need buying. If you have neither, you're not playing the game well enough.
3. Poor AI
No contest. The AI is astoundingly poor. The only defense I can put up here is that it is about as competent as Civ IV AI, which was also really bad. This is not unusual for any Civ game, actually.
The difference is that Civ V is more complex than Civ IV, so there's more chances for the AI to screw up. Thus, it is more obvious that it's bad.
4. I don't consider the transparent diplomacy plays of Civ IV to be interesting. Real players don't tell you why they're behaving the way they are. They can attack you out of the blue just because you look weak. Civ V's opaque diplomacy approaches real players more than Civ IV's BTS AI. I don't consider this a step back as a step to another ideal. I did not like the transparency in Civ IV as it made it harder to pretend that you were not playing a single player game.
5. The cultural victory can be attained even when you have large empires. In fact, it's easiest currently with large empires, and that needs a fix. Smaller empires need to be more competitive.
6. Sullla makes the mistaken notion that ICS is in Civ V, much as it was in Civ III. This is not the case. In order to make ICS as profitable as he makes it out to be, you need 2 high-era policies at the end of their respective policy trees. This requires that you beeline Industrial Era and save up all policy points while doing so. You can't really do that while doing ICS. You can do ICS afterwards, though, though that is not materially different from how Civ IV allows you to do this with Corporations.
He is trying to paint this in a negative light because he does not like Civ V. In fact, it's neutral.
Being able to support fast-growing, quickly productive cities means that you can shift out of a Cultural small-empire focus very, very quickly in Civ V, and resort to Domination or Diplomatic wins, if that is your goal. The shift is quite dramatic, easily more plausible than you could even in Civ IV.
You just need to know how to do it.
That really sums up many things that I routinely find people complain about in Civ V. I have no shortage of criticisms about the game. I feel that it is in a raw state, primarily because it's really built from the ground up - a new way to look at the Civ game. Civ IV was the apotheosis of a game concept that started in Civ I. Civ V introduces a lot of new concepts, and it takes a while to get them right. It's pretty good for such a game.
That said, many negative comments about Civ V are just flatly, factually wrong.