Well that is your issue , restriction, except yours is space and mine is money. You can't have or do any more so you come to a dead end and stuck there long enough you get bored.Haha, room isn't big enough.
The larger tank option is a no go, I already have as much tank space in the house as is possible
Replace the fish and perhaps get rid of the bookshelf.
If I was unrestricted I would have the whole wall from left to right and top to bottom one huge tank but like I mention not just restriction causing issues, you have to be sensible and compromise. Throw the kids out or make them share then you have a fish room and so on. Sell the kids on Ebay and buy panaque.