Tyre wise, I use gravelking sks, they're great off road and none too sluggish on it. What's your budget for new wheels? Maybe summat like dt Swiss r460 rims with the best hubs you can afford. I run mavic a719 rims on Shimano xt hubs, not light, but then they are on a Surly Cross Check, so it doesn't matter, and it's the most enjoyable bike I've owned (and I've owned a few).
Saddle wise, just use what your bum likes and what you like the look of (secondary importance, as most of the time you can't see it).
Tyre wise, I use gravelking sks, they're great off road and none too sluggish on it. What's your budget for new wheels? Maybe summat like dt Swiss r460 rims with the best hubs you can afford. I run mavic a719 rims on Shimano xt hubs, not light, but then they are on a Surly Cross Check, so it doesn't matter, and it's the most enjoyable bike I've owned (and I've owned a few).
Saddle wise, just use what your bum likes and what you like the look of (secondary importance, as most of the time you can't see it).