so for the early game my answer is YES!

farmers are baâaaad

i systematicly put one famer on my 1 cities
as soon as it reaches 2 i see if the increase of food is better than 30 or 40% i let the farmer, if not i leave it. Sometimes, when the citie is in a bad place(hills, forests, swamp, moutains, desert...) i put 2 farmers.
When the cities reaches 3 and 4 i let 1 farmer only if the base growth is under 600 or 700

and there is an acception(which confirm the rule ) my wonder citie
In order to build the ramayana and pyramids(the only 2 wonder in my mind who are essential to whin in that difficulty lvl) u have to settle a citie who will do only wonders! I put famers at thier max until it reaches 5 or 6(depends on the tiles arounds, the goal is maximize the shields as soon as the growth is stoped)
that's the easiest way to have a productive citie in the early turn of the game