This is awesome that you've added my idea :D (on a side note - was able to pass 50 wave with #5 Update active playing and some more upgrades, кажется я начал понимать как в нее играть)
Will try to keep numbers of my ideas, so you could track relation.
2) Based on 'you were able to implement it and it is working!' - i have kind of extension\rework to this idea (just ignore this if it is too much):
i've noticed you have preset positions for buildings (18 in total) and they are placed randomly at the beginning - there is a total of 12 crossings of "roads" (free spaces) between buildings (hope you understand what positions i mean) - if you could define these as places for towers and place them randomly like buildings, this could be even more interesting to handle i think.
For more randomness - define cross-area (like +, 5 possible positions in it) with center on those 12 positions and make 2 random drops - first defines which of 12 crosses used for each tower, second one position inside that cross. Надеюсь не слишком загнул :)
You can place 9 towers in the beginning with related buildings (in much later game you'll be able to fill all 12 with Tower Slot upgrade, unless there will be someone stacking up first 5000 Stone for just this purpose), so some places still might remain undefended.
6) Please create FAQ topic and GameMechanics, so you'll be first there and everyone would see your message with useful info. I have some questions that i will post after, for you to explain if you have time :)
7) Cut down the number of artifacts to just '1 per bonus type' and make their effects scale with Fame lvl. Also some specific sets of Artifacts appear with more chance depending on selected Speciality.
8) Not sure if possible at all but - click-hold to build multiple Walls, so it is built once it becomes "green"... or holding Shift to keep selected building for construction. Filling everything around the Core with Walls is very time-consuming :D