metal driver/soft dome, both can be harsh hs nothing to do with the material. A lot of folks get mixed up detail and harshness, if you're not used to it detail can come across as cold and bright.
As you say Arcam traditionally (that's an important word newer Arcam is a very different sound to 20 years ago) is a smoother listen, to bring some pep back you want
more lively speakers. Its about balance you don't want to much of any one thing.
Speaking of Klipsch and a lively presentation id add the 600rp bookshelves to your short list, they need a boundary wall so can sit quite close to the wall behind them.
Others too lookout for second hand
revel
neat
older missions 780s and up just make sure they went back for the mid range driver recall
JBL
KEF coda i quite liked these back in the day
KEF iq5's very nice especially the special edition versions
new
KEF
BW
Qacoustics
wharfdale
never heard focal
Try and audition those