I would plump for the 1904/1905 season. Around 45 friendlies with no league table to worry about plus a match to try to qualify for the FA Cup. Playing at home on a couple of different grounds and giving Hull it's first taste of a competitive round ball game. Am sure it would have been a very relaxed and enjoyable time.
Kicked out of the Boulevard, despite paying a 3 year rent, having to play on a cricket pitch, running up big debts in the course of the 'friendly' season..... A tense first year I'd say.
someone earlier mentioned the "Div 2" years from 66/67 until we got relegated in the late 70s. we only had one serious look at promotion. We were never really in the relegation battle until the final season. there was a dearth of decent cup runs. Interest and attendances plummeted. I think I am correct in saying we set a record for the most consecutive seasons (*) in the 2nd flight without going up or down (or in Leeds' case, being expelled mid season). Those seasons were pretty stress free for the most. Shame it was the period when I attended most games. (*) Or it might have been that we had been in Div 2 for the most seasons by the time we were relegated in that particular stay. Every other team we had played had been promoted or relegated in that time.