So I'd heard, from time-to-time, about these players who have hundreds, or even thousands, of extra settlers in their star menu. I was always a bit dubious of such claims, but thought I'd take some time & see how long it really took to accumulate that much extra population. The results are below, and show 17 full stacks of 625 settlers, plus some remnants and the 20 I received as my daily login bonus today.
It took me over a week of minimal adventuring to accomplish this. I've done 4 or 5 loot spots, losing 200 ~ 250 troops each time, as well as 4 Horseback adventures, losing a bit over 1,600 troops (Recruits & Bowmen), along the way. My current population is full, though it's hidden behind my avatar. On each of the loot spots I received 300 settlers, so killing those troops actually added to my excess capacity.
Along the way, I still managed to produce more than 150 baskets & 75 sandwiches per day, and keep my 5 fishermen and 8 hunters fully stocked w/20k plus in their deposits.
So if you're wondering whether it's useful to upgrade your Provision House, my answer is an unequivical YES! A stack of baskets pops out in 2.5 hours. Sell them at 6g each and your Provision House is making 60g/hr. Settlers take less than 4 hours per stack, which means you can replace those lost troops ever so much faster & do more adventuring.