NinjaDeathSlap said:
- the epic story, and richly detailed mythology behind it are still present
- there is still a strong emphasis on characterisation
- the Galaxy Map still makes the world feel appropriately huge
- the environments are varied and richly detailed
- the vast dialogue trees are still their and (most) are relevant and interesting
- the side missions still have a non-linear focus and vary greatly in length and importance
- your abilities and equipment still progress as you progress further in the story
Firstly, only the last two have anything to do with the video game genre "RPG." One of the things you have to understand here is that the video game term RPG Cannot actually be summed up as its abbreviation for "Role Playing Game," Otherwise every game where you take the role of a character would be considered an RPG. As such, the background of the game, the characters, the size of the world, the environments and the dialog, do not have anything to do with the RPG genre.
Equipment "Progresses" in the sense that you get some useful, though low impact, upgrades to weapon types as well as new weapons for that type placed sporatically throughout the game world, a vast majority of which are a trade-off instead of a straight upgrade (a sniper rifle with more bullets per clip but less damage per shot for example). Overall, this doesn't create a deep sense of progress. It's there, but it's not as obvious or fulfilling.
Which brings me to the abilities, which act the same way. You get some useful, if again low impact, upgrades to skills (and only to skills) which eventually leads to a more obvious upgrade, but aside from unlocking the skills to use in the first place do you ever notice this? do you ever care about it? Do you play a different way or use different skills because they were upgraded or do you mostly stick to the same strategy regardless of how you've been spending those upgrade points? It's a shallow system that doesn't have a very big impact on things.
And to elaborate on that earlier complaint, that you can only upgrade skills, I'll tell you what (to me at least) makes or breaks an RPG, progress of the character. In the first ME (which was hardly the deepest RPG in the world itself don't get me wrong) you could spend upgrade points on various combat skills, the ability to hack things or decrypt messages, the ability to persuade or intimidate people, or, and most importantly to my point, general statistics. How good you are at using a gun, how much protection that armor gives you, that is determined by the points you spent in the first ME. In ME2 Shepard is shooting just as well the moment he wakes up from being revived to the last where he's firing at a baby reaper, the player behind him may have gotten better with the gun but Shepard hasn't. Statistically, Shepard hasn't advanced in the slightest.
And that's where the problem is. All of the advancement and progress, admittedly baring the abilities, is going on around Shepard. He gets new guns or nondescriptly upgrades them, he buys a nominal new piece of armor, but Shepard himself does not feel like he's advancing at all, and that's where the issue is.