For me nothing comes close as what Shogun (the original) did. While the graphics haven't aged well...the campaign map, the units as chess pieces on the map , the harvest that provided you your big income once a year and you had to have it last for 3 turns keeping your units up. The little cutscenes with agents, the diplomacy room.... that game just had so much immersive flavour which I've yet seen recreated in any other game with the exception of Medieval Total War (2002) but..... my favorite campaign goes to Medieval Total War 2 : Kingdoms and specifcily the Teutonic Campaign.
Shogun 2 came really close , it had some things I really liked about it some things I didn't but overal I hold it in high regard in the series. A bit biased because I'm a big sucker for Feudal Japan
so I take a lot of it granted.
And as you put it , it comes down to flavour of not just the time period but also what it does with the campaign mechanics and battle mechanics. I have been eyeballing the WH side of it as well , I like the lore enough thought not that well versed with it and perhaps I find the newer mechanics fit better in a Fantasy setting then a historical setting. Who knows that I might be poised to grab one with a sale which are plenty throughout the year.
As for the Remaster, my main reason was to get it so I could play Rome Total War again which the original didn't do so well on my modern rig and it came with Alexander expansion which I never gotten so there's that to explore.