I didn't feel this way about 4E at all. It felt restrictive. It relied on extremely limited mechanics. Worst of all, it was repetitive. Every fight went nearly the same with a character blowing off encounter powers with an occasional daily worked in. People selected for the best abilities as is common to these games. There was very little differentiation amongst casters because nearly everything was damage based and slightly different derivative of another power based on the character's main stat.
Yeah, I liked the way that everyone was 'playing the same game' when it came to the mechanics of defeating things. The whole 1e Assassin thing where you just killed things in one blow (albeit there were restrictions, it wasn't easy) was just bizarre. Blungo the Great, swordsman extraordinaire couldn't possibly kill a dragon in one shot with even the most extreme luck, but his buddy the assassin could insta-gank it with a dagger. Just never worked for me.
As far as 'same combat' went. Well, in any edition of D&D if you had say a bunch of orcs in a fairly featureless room things would pretty much go about the same. Now, in 4e you could create some complicated terrain, give the orcs a ballista, set up some sort of goal other than killing them all using an SC or etc. Obviously none of this is IMPOSSIBLE in AD&D either, but 4e had some pretty nice rules for it. We just didn't play bland vanilla encounters over and over again. I realize that 4e adventures and, apparently, most DMs literally did that, they just duplicated the same 5 or 6 encounter templates again and again with only minor variations. Its a shame. When you fill the game with Indiana Jones-esque crazy stuff it really works incredibly well.
I never thought of any of the rules as being 'in the way', they just added a whole new dimension that wasn't really there in AD&D where any kind of stunt or etc was just totally 'out there' and unless you had spells a fight was just "I hit it again".
You felt like that was heroic fantasy more so than Patfhinder/3E where you could build a more complex and complete strategy with a vastly more complex and interesting use of spells. I have no idea how that last statement doesn't apply to every edition of D&D. I do not see how you could argue on the basis of mechanics that 4E was more open-ended than previous editions of D&D or the current one. In fact, you could probably empirically prove that it was less open-ended due to the structure of its combat system. Character creation and powers were very limited in scope.
Yes, all RPGs are in some sense open-ended, but what I mean is 4e has a set of rules frameworks and material that sits in them for a very wide variety of things, much wider than what even 3e has. I don't think you can 'empirically prove' anything about an RPG, so lets not try.
Why does 4e have heroic fantasy? I can have my fighter run up to a chasm, leap across, and take a huge roundhouse blow at the dragon, and then another similar blow, and I can do that at level 1 and without even improvising. Oh, but most importantly, I know the odds of it working, and I know the implications of being in melee with that dragon, and I know I can probably at least survive the consequences of failure if I'm at full strength. My AD&D character? He's probably toast, I don't know how far he can jump, but if he falls short he'll probably break his neck in the fall, and in any case even a couple dice of damage is a big deal. My 1e fighter hacked at things and mostly got in the way of them ganking the wizard, my 4e fighter leaps, makes amazing attacks when the chips are down, gets back up after having his arm half-bitten off, etc. I call that heroic.
Were you really not that creative in 3E? The open-endedness and options in 3E were nearly endless. You had a huge number of actions codified while still allowing for improvisation that lead to outside the box thinking. I allowed things like a wizard to modify a fireball on the fly using Spellcraft to create a wind effect to clear a gas cloud or a really strong fighter to hurl a person up a 30 or 40 foot wall by virtue of their strength. I don't see any reason to believe 4E accomplished this in any better fashion than previous editions.
Well, 3e at least has a d20 core mechanic much like 4e's, so in that sense improvisation is at least supplied with SOME mechanics. 4e's version just couples that with a healing, hit point, action surge, etc mechanics that highlight the 'do heroic things' part of the game.
As for all those examples, you can modify a spell (or other power) in 4e, do any improvised action, use a skill, or perform a whole skill challenge. These are all quite well-supported concepts. The thing is, with the short list of skills you aren't wondering which one might apply, or being saddled with a lot of useless ones that never do. With the SC system you can know the stakes pretty well. Powers provide a great universal framework for 'things characters do', one that offers a lot of possible options in terms of house ruling, improvising, making interesting items, etc. Its just a system that covers a LOT of stuff and happened to deliver that kinda crazy superheros sort of game that I always envisaged.
The only parts of 4E I looked at as innovative were the skill stunting as long as you didn't use it too often and make the reasons it worked absurd. The open-ended monster creation which they transferred to 5E in a very easy to use format. I found the character creation system stunted and very lacking in creativity. Character creation went from extremely open-ended in 3E to extremely closed in 4E. It seems to be somewhere in-between in 5E.
I think CHARACTER POWER and EXPLOITABILITY of the character creation system were extreme in 3e, and much more dialed in in 4e, but you can support all of the same character concepts in either edition, and they will work pretty well in both. 5e is REALLY much more like 2e in this sense. It has pretty limited options, but you can add on backgrounds and you get a subclass at 2nd/3rd level that gives you some more choices. If you want to use MCing then it gets a bit closer to 3e, but the 5e classes aren't as generic and flexible as the 3e ones.
The 4e character system has a crazy amount of stuff you can do. Just power selection by itself is a huge ways beyond any 3.x derived system. EVERY 4e fighter is unique, and that uniqueness WILL show in combat (and probably elsewhere).
That's how I see it anyway. Unfortunately for people like me this is why 5e 'sucks', it definitely doesn't cater so well to the high action kind of game. Its not quite the gritty low-fantasy grinder that 1e was and 2e could be if you played it that way. At the same time it feels a lot more like low fantasy and a lot less like you're really a fantastical character, at least for the first 6 levels.