I think the combination of woodburning and pellet is a good belt and braces combo, unless you’re very short of suitable storage space for the latter (pellets, not braces). However, if you’re not here much in the colder months, presumably you don’t need that much fuel.
I was initially sceptical about pellet stoves, but have been convinced by several friends who have them and so we’ve just bought a 9KW Italian one to heat the middle floor of our house. There’s a 9KW woodburner on the ground floor that was cheap to buy, but very expensive to install (it also heats two bedrooms on the top floor) We also have four heat pumps, but only occasionally use their heating option and then for just a few minutes. However their dehumidifier is very useful when the temp gets above 40° (and more comfortable than the a/c) .
Our stove including ducting was half price in the French sales and the installation is very simple as we’re able to run the exhaust through a disused mediaeval chimney that was unsuitable for the log burner.
I don’t know anything about UK prices, but might you be liable for import duty if you brought one into France? If you’re not a French tax payer, you can’t claim a rebate for your pellet stove, but this site had a number of good deals
https://www.poeleaboismaison.com/pack-promo-poele-a-granules-etanche-emaflam-nala-9-kw-blanc-kit-ventouse.html