Check-in:
My experience with EasyJet was that they had a limited number of queues available, and the one for my flight (STN -> CPH) didn't open until about 90 minutes prior to the flight--until then, it had been for a different flight altogether. I was surprised at how not-terribly busy the EasyJet counters were at STN; although there did become quite a line for my flight once they opened the check-in counters, it was extremely calm. I usually can't stand being in lines at airports, but this one seemed tolerable.

Baggage allowances:
Having first flown Ryanair, who's extremely diligent about charging for baggage overages on their flights, we were expecting to pay through the nose for our overweight bags again. However, EasyJet allows more than Ryanair (20kg on EasyJet vs. 15kg on Ryanair, I believe), and even though our bags were all slightly overweight at check-in (about 22-23 kgs each), there was no mention of the surcharges by the desk agent; she just put the "Heavy" tag on the bags and handed us our boarding passes.