I'm disappointed for you that you've had such a poor experience with C2, but if it's not for you, then it's not for you (sorry for the tautology).
I've tried most game creation systems, and this is by far the most accessible in my opinion, and allowed me to fulfil my main ambition - to re-create old classics from the speccy and amiga days (no interest at all in mobile).
If you give us an idea what you are interested in doing with the software, then we may be able to offer a more tailored response.
For instance - I love point 'n' click adventures, and I don't think you can beat Unity with the Adventure Creator addon.
oh yes, C2 is great, thats for sure. I mean look at some of the stuff people show in the "what are you working on" thread. Its truly stunning and shows in the right hands C2 is great.
What am I interested in? well, creating very basic games but a variety of them, say anything from a fruit machine to a pinball game to a clone of Spectrum's Jetpac, Manic Miner or Jumping Jack, to a clone of the Atari 2600's Adventure or the Arcade Scramble, Lunar Rescue or If I'm really adventurous Mr Do.
If I'm being totally honest here my "main" problem is that things that you would assume to be simple are HUGE issues and take me days to resolve ..or never. I can't start a thread here asking for help every time I hit these problems as I'd be banned for spamming for forums so much. heh
a couple of recent examples:- I was working on a really simple tank combat game, rather like the old Atari 2600 combat. and setting up the play area was simple, making the tank rotate and aim for the pointer again simple, collision detection for your and the enemies shells? simple. (something I'd assume would be hard) but then I spent 4 days solid stuck on something as silly and dumb as adding an extra life every 1000 points, then I'd get stuck on why the score and lives weren't resetting on a new game.. that took me 3 days to resolve. and why my enemy tanks only fired once and never again? (that I never solved)
Then I'd had enough of that game and started on a batatelle game (simple game, you shoot a ball up the screen "pinball like" and it bounces off various things and lands into scoring zones) sounds simple huh?
Well it took me 2 days of work to get the ball working properly, although I never did quite get the "hold space down to shoot the ball harder" working and I then wanted the ball to stay where it landed and you spawn a new ball but alas no, I couldn't figure that out and after I followed several tutorials including one on this site on how to save your high scores, I could never get it working.
Sorry for a long winded post, just trying to explain the fault here is not the software but my lack of intellect/education/maths schooling and 53 year old brain. I have ideas for lots of games but sadly actually creating them seems to not be my thing and like I said, I doubt me creating 10 "help me" threads a week would be a good idea
btw.. you can see I'm almost as bad explaining things as I am at programming.