Thanks PP. Interesting re the pricing via SNCF. An English friend of mine who now lives near my place in France makes the mistake of waiting for TGV tickets to be released before booking Eurostar, but by that time a lot of the Eurostar trains are very expensive. I've got into the habit of buying them 6 months ahead, when the bulk are £57ish direct from Eurostar, but next time I'll look at the SNCF option too to see what price they are offering. The SNCF website is, erm, 'quirky' at times (i.e. impenetrable what it's up to), so I've not tended to use it for more than SNCF tickets.
Re baggage pricing, I knew they did that on Ouigo trains (not that I ever have anything more than a rucksack), but hadn't realised they've started that on ordinary TGV trains too. Though, TBH, I'm not surprised, as some people really take the mickey with how much luggage they take, leading to slow loading of TGVs at stations, and dangerous amounts of baggage in carriages.