Hey guys
So i have been Android developer for multiple years. I develop using the good old eclipse and I do mostly tools. I did some very simple based turn games using either canvas or drawable views 
At this point I am making another game (2D).half way through development, my partner keeps suggesting that we should go with an engine to handle graphics better and bevause the game will get more complicated. It is still 2D game and the screen will just have little characters moving around and performing fight (imagine clash of clans). Some buildings, some characters moving around and click able states.
The other screens are basically either “entry screen with buttons” or 'exit screens". These other screens were coded and look nice
Here are my questions (given that I never used a game engine before)
1-given the above description, is it worth it to go with game engine or (game make studio)? This includes the learning curve of it
2-i want to utilize as much what I have as possible. Is there a game engine that will let me keep the screens that I built and use the engine for only the game play screen?
Your input is highly appreciated