You sound like a better computer guy than me [...]
Nah... this is just right exactly in my wheelhouse. I have been making portable miniwins since Win31 days... It has been an ongoing part of my tech support milieu, especially since win2k came out without a boot disk. I am still supporting a miniwin7 and have a mini10, but it is still kinda a work in progress... I am using it now, because it detects better than Win7, but the Win7mini is tried and true...
So anyway, making a Win10Slim is just playing around for me :) The trick is how skinny can you make it and still maintain full capability.
I did take over kids computers for a couple days to remove all the junk of Win10 I could find (lot of searching for what needed to be deleted).... They really know how to bloat up software now days, no wonder they need such super processors with Ram out the yahoo.
I am pretty handy at that... If you need a hand with it, let me know.
Always liked the Pale Moon and IceDragon browsers (both worked off an earlier Firefox build)... Mainly because I liked the add-ons folks made for them. I don't have to have anything fancy, but I be dang if I am gonna browse without an adblock program. That I have to have. I like privacy so I have a cookie eater/blocker program, and a flashblock program that toggles on and off as needed (w/ whitelist).
I am stuck on browsers... I mean, I have grown steadily attached to FF since it began syncing... I have been a FF guy ever since they started up. I recently began moving over to Chrome, just for the speed....but even at that, I am loathe to even mess with anything else - even Opera, which is a Google owned browser now too (and even faster than Chrome)...
All was going fine until everyone started switching to HTML5 exclusively, and people started dropping support for browser updates. I was losing some of the streaming ability (Fox News and others)... but this new browser has gave me back that ability. I am happy...
Secret to long computer life, good fan, and blowing out the dust every few months with an air hose.
Yeah, I wouldn't have the patience for it... The minute I am fighting to keep it alive, I am going to something else... Computers are SO CHEAP now... The box that runs my main TV is an old Dell I picked up for somewhere between $50 and $70 bucks... and it's a 4-core i5 with 8 gigs of ram. All it needed was a HDD and a reload and zoom baby! I have since converted it to Win10/64, and it is the main media server for the house...
With that as an example, why would I suffer an old box for a mere pittance like that? As it turns out, The machine I retired form that station went to power the TV in the bedroom, and I sold the 2 core machine from that station for 50 bucks, so I am really not out much at all, other than elbow grease. Why fight it?

There is thrift, but sometimes you can chase it too far. The sweet spot is when you can sell your outgoing gear for enough to supplement the incoming gear... And I actually wind up cheaper doing that. At least most of the time.