Although I'm not active developer anymore, but I remember many times when developing mini-games gave me headache because of so many repeating lines of code. Luckily the frameworks are here to help, but unfortunately there is no framework for PocketMine. Long story short, I am developing new mini-game framework called Quickex. I have put two day of brainstorm in it right now and it's obviously a mess and I want user feedback of it. Framework: Quickex Plugin built upon it: TDM-Quickex If this framework doesn't get enough user attention, that's ok. I'll still be developing it myself. Note: Framework is in heavy-development and is just a concept at this state
Fun fact: There is no working framework for PocketMine according to https://github.com/search?utf8=✓&q=PocketMine+Framework.