I have a similar problem, but it differs significantly in what I can afford to buy. I need one new game that I want to be made in the next 3-5 years. I have one space left in the gameroom, and it will be at least 3 years until I can afford to fill that space.
I have no desire for old games these days. AC/DC, Metallica, and AFMr are the only new titles I have wanted bad enough to buy in the last 4 years. AC/DC was sold a while back so I could put some money into toys outside of pinball. GnR is the only other pin I have. I could see trading that one for an MMr someday, but probably not for a while.
I need the next game I buy to be at least as good as the ones I have now, and that is a tall order. I am not sure even AFM makes it to the level of Metallica for me, so the bar is high. I am to the point that buying nothing is an ok option if there is nothing that I absolutely need to have.