Now that you've advanced several regions away from your Home region, you should consider building some Forts in key locations. Look at where you're wanting to go (your nearest enemy, a grouping of Plains Regions, a forest region for cloaking purposes etc)
Place your Forts inline so that you can summon more Lessers to support your expansion.

As a general rule, Forts should be built no closer than three regions from each other, So you should be able to count to the third region from your Home and build a Fort there, however, There are always exceptions to this guideline (very active fronts, Fury Farms, etc)
Placing Forts too close together on a regular basis not only wastes Treasure, it will actually slow your expansion by "wasting" Treasure on extra Forts that could have been spent on Lessers, Temples, or Fury Farms, so build wisely, and keep growing!

In the early stages of your expansion, theres no real need to Take every region, sometimes, you can bypass a region or two in an effort to extend your initial front as far as possible, picking up these regions with a 2nd or even 3rd wave of troops.
Forest regions are the ideal regions to skip as they only bring in 2T per tick, other considerations are regions with 1, 2 or even 0 natives in them, send only enough to take the region & put the rest with a larger group that bypasses it.
yet another option is to set predefined borders with you Nap partners & send a large force toward your enemies while sending smaller groups to pick up these "safe" regions at your leisure.