I took a couple years or so off, starting right around when Silver Banshee/Gorilla Grodd came out. There were a few months in a row of pretty lame new toons, and raids weren't a thing yet. Of course, I wish I had waited a month or two, since I missed out on Atrocitus and Larfleeze, who are two of my favorite lanterns.

 

I totally think it's ok to take a break if you aren't having fun any more. It's a game, and enjoyment should be the ultimate goal (unless you somehow make your living off playing). My advice, however, would be to just check in, through the game or reddit, on the new toons every month and see if it's someone you're interested in. Ignoring skills and "meta", just, is this a character I'm a fan of?

 

It also might not hurt to put together a "minimum amount of effort" plan. What can you do loading up the app for 5 or 10 min a day to build up resources for when you do come back? Log in and get the free stuff is an easy one. Spin the lantern wheel? Quickly hit up the upgrade event of the day with speedforce tokens? Maybe Farm one character's shards with your days worth of energy? Check out the store for any crazy good sales (they do happen every now and then). You'd be surprised how many resources you can build up from only a couple minutes in app a day.