For a couple on a busy route like Venice, I'd say yes.

a) You get a hot meal in Club on Italy routes, unlike the cold salad on France / Germany etc. Plus 2 hours to drink the champagne.

b) Assuming you can get seats on the left hand side (OLCI as soon as you can) they you'll have a row to yourself (2-3 seating) with the gap in the middle for newspapers etc - in Economy, there is likely to be someone else sitting with you as its 3-3.

c) The Gatwick lounge is good. Although the Priority Pass lounge at LGW (the Delta lounge, which is directly below the BA one) is also very very good, so you're fine either way.

Others on here have reported that the CE service from Gatwick is worse than it was - I can't really comment as haven't gone ex-LGW for a while. Put it this way, though - compared to what you'll pay for a dark, tiny hotel room in Venice, £50 for CE is a real bargain!

(PS. Try the Giorgione hotel. Generally regarded as the best value four star in Venice at c€140 in low season. A bit flowery but good value. About 6-7 years ago the tourist office at the airport put me in the most disgusting 2 star place imaginable. Desperate to escape after 1 night (these people made their coffee in a saucepan on a stove!) I burst into the very-posh-looking Giorgione two doors down prepared to pay whatever was required to leave my current place. I was shocked to find they only wanted about £10 a night more than I was already paying for the hovel I was in! Recent tripadvisor reviews show it still seems to be a good place.)