OK I call BS:
There's a lot of awkward inconsistencies such as sometimes when you download a game from the store you get an unlock file, and others you get the full game, and other times you get random extra downloads on top, then it's non-obvious what files you can delete so you end up with these files that do nothing but you're unsure if it's safe to delete them.
This shows you have never actually used a PS3. After installation, there is just "the game". "Game data" and "Patch/DLC" may exist at some point, but only if you have run the game or downloaded them. These are all clearly labeled (assuming you know the definition of "DLC" or "Settings") and in a single location with the same game icon. There are no "files" that are "non-obvious".
For games where you download a demo and an unlock, these are merged into a single, unambiguous game. There is not even a separate "game data" at this point. From your description, it sounds like you saw someone download a demo, a game, and some DLC, and thought these were somehow all required to run the game.
While the demo+key solution may not seem like the most elegant, it's pretty nice when you try a game, decide you like it, and then don't have to spend another hour redownloading the full version .. you can just unlock it and continue playing in a minute or few total.
I do feel that objectively the 360 feels more polished, the controllers not only feel better to hold and use, but the PS3 buttons even just outright feel like they don't respond sometimes.
This is not "objective". Subjectively, to you, the 360 feels "more polished" and the controller "feels better to hold". I have the opposite experience; the 360's controller is OK, but I prefer the DualShock (and I have big hands). This is the first time I have ever heard of a non-broken PS3 controller feeling "like they don't respond sometimes".
Patching is horrendous, I had to download many 10s of gigabytes of patches for the handful of games I bought
OK at this point it's clear we're dealing with FUD. The biggest patch I've ever seen was around 200MB. The biggest downloadable full game I've ever seen is 14GB (though I typically buy discs .. infamous 2 was free for PS+). Never have these required "10s of gigabytes of patches".
The sign up process to Sony online was brutal, the site kept going down and I desperately tried to recover an SOE account from years ago but apparently that's a different Sony online thing to the Playstation one and that made it all a bit of a pain.
Er... so filling in a few blanks on the screen was "brutal"? I suppose if you're really a cluebie, you might confuse SOE and PSN, but nowhere is SOE or an SOE account mentioned in the signup process. Perhaps it would be nice if they merged these at some point, but that would get its own share of complaints. And let me tell you about the "recovery" process for XBOX/GFWL accounts...
In any case, this entire rant comes off either FUD, an incredibly inexperienced user, or someone who uses a 360 and watched their kids using a PS3.