I'm seriously looking to trade locally first before messing with Canada Post. Anyone in here from Winnipeg, friend me.

Absolutely this.
I actually have about 3 different PO locations I go to, depending on what I'm sending. One place charges me lettermail prices for padded envelopes (dice, etc.) instead of small packet prices.
That same place, however, won't charge small packet for the 4" boxes - unless I stuff said box into a big, padded envelope. Which is stupid, so I send those from a different place that's a bit more lenient in that respect.
Haven't yet sent anything with the new rates though.
Since I have a bunch of stuff I intend to sell off ASAP (clix, 1980's D&D figures, G1 Transformers), I should really look into that before I potentially lose money on shipping costs.
Tracking to the US, you say? That's kind of nice.