So I have a bit of a problem I was looking for advice on.

Context: I am playing a custom nation in NA (I know they're not really playable but bear with me). In order to solve a huge horde of tribals from low centralization (American Democracy) I had to urbanize large swaths of otherwise good farming land in in the Northeast coast.

Problem: This normally would be fine, but the extent of urbanization ground literally all development to a halt, and my tech is significantly lagged due to not getting institutions yet from European colonials. I'm at 80% extra food utilization in the Northeast and 70% in the Southeast.

What I've done so far: built warehouses in my largest cities, which seemed to help the populations continue to grow, but didn't alleviate the regional backlog.

2 possible solutions I considered: 1) Save up and build a few canals on my highest fertility provinces just for the food (even though they'll be extremely expensive due to the fertility) 2) continue to expand into other high fertility regions to find a continental food source I can at least profit modestly from as it sucks my city wealth dry.

Which of my two solutions is preferable/most cost effective? Are there other potential solutions I'm not considering? Thanks for the help.