I’ve tried some weird and wonderful partition schemes in the past, but I think I’ve settled down and just go for simplicity. Half a gig for /boot, and the rest for / (in ext4). I’ve tried btrfs, but I’ve never been in the position where I needed snapshots, and ext4 is a lot more simple.
I also like having the flexibility of not having a separate home partition. I back up my super important files, so it doesn’t matter if I lose home (not that I distrohop much anymore, anyway). And I don’t have to stress about whether I’ve made my root partition big enough. For the same reason I use a swapfile rather than a swap partition (though I do need to look in to zram and zswap) - I like knowing that I can resize it easily, even if I don’t really plan on doing so.
I’d suggest you may be better off not bringing your phone at all, in this case.