In reply to mike123:
We've stay at Reims too, in a Hotel Premiere Classe - there are at three there (and from memory Reims Nord is a bit newer, but not quite so convenient, but does have a secure car park). They're a step up from F1, though don't expect the Hilton. Alternatively Campanile are a further step up, and often adjacent to a Premiere Classe.
I'd do the tunnel over ferry - we've done both, and the ferry is often delayed, and is slower. It wasn't so bad when DFDS had a more frequent service as they'd let you onto a slightly later or earlier boat, even on their cheap tickets, but last time I looked in early 2020 they'd reduced the number of sailings to the extent that this policy was moot. Eurotunnel, on the other hand, let you rock up about two hours either side of your booking and will put you on the next train for no extra charge - their website's a bit coy about this, and it is discretionary, but we've never had a problem (even when everyone was panicking and trying to get back to England on the day the French closed their borders in 2020).