I'm doing the opposite: increasing collection to perhaps 5 or 6, while reducing overall value significantly. Why? Because I do like a bit of variety, but mainly because the law of diminishing returns sets in remarkably quickly, especially with so many unremarkable watches now making as much as a decent used car. There are, quite simply, plenty of watches in the £50-200 range that I'm very happy to own and wear.
I also think that there's a big bubble, and that trading higher value watches, here or elsewhere, is just too risky/too much hassle for me these days. So it's strictly pocket money deals for me.