Downgrading

18k in the hands of an experinced listener can go pretty far if you factor in used prices. It won`t out perform any and all 100K systems but would equal and beat some of them.Some very exspensive systems sound stunning and there are others that sound rather poor.
Regards,

When I sold off a pricey tube amp and tube Pre-amp, I then bought an integrated amp (also tubes) and pocketed thousands. I thought I was downgrading. Funny thing- it was quickly apparent that the integrated amp sounded better. I call that a win-win.

As far as digital- something that may have been tops a decade ago is often easily outperformed now at lower cost.

Simplifing can be a good thing; my new passive pre is an upgrade to me. But it was well chosen and not cheap. Constant tuning is the price of progress.

IT is easy to go past your goal; a good idea to back off a little from time to time.

Don't confuse down grading with down sizing. Down grading means crappier sound, if your into that, go for it. From looking at your system link, I think your at the bottom of the food chain already.