I don't see how one could not get bored with fish keeping or any hobby from time to time. Especially when ones got a busy schedule.
I had many smaller tanks, then down to 1 large tank, and now back up to 4, all large. I find larger tanks much easier to maintain for some reason. I just hook up my 1" PVC drain system. I have all my tanks in one room, and I can drain them all before I can fill one back up. Large tanks, light stocking and light feedings. A nice sitting area to sit and chill I could stare for quite awhile on some days. Sometimes I don't sit down at all. I love my stocking though and am enjoying growing them out. I like rearranging the scape from time to time too.
That's prob the main problem with my 75.. It's in a kinda off room since it was the best place to put it so I don't get to enjoy it nearly as much. My room is completely full due to a large couch being in it ( it's my moms $4000 couch so getting rid of it isn't an option)