I would begin by simplifying and reorganizing the plantings. The picture shows a general organizational scheme. Where you have groundcovers, they need to be solid, not a circle of plants at the edge or a bunch of odds and ends looking plants. The large tree island should be larger with a smoother, more uniform outline.

I can't really see the detail well, but where the shrub is below the overhang, you may be able to pull it farther out from the house where it can get more light and water. At the right side overhang, maybe use just groundcover.

Yardvaard, thanks so much for taking the time to do the rendering!

- We were debating widening the front tree planting; I like your visual of it!

- Addl questions/refinement (added another closer pic so you can hopefully see more detail):

-- The red tree to the right you mention pulling back to a regular circle and doing plain groundcover as well. We have 2 protruding pipes towards the bottom (nearer the 3 bushes) and will need to keep it elongated to cover it. As it's a very large area, I would like to have some type of colorful interest there, with perhaps a groundcover in the middle, keeping the three red bushes if possible (they were a gift). Is there a design you would suggest?

-- Your drawing shows groundcover for the overhang/window on the right, and a single bush for the one on the left. The area is large, about 11 feet from the rightmost post/porch edge to the brick wall, and almost double from the window to the edge of the walk. The bed to the left is even larger. Won't a single groundcover on one side and a single bush on the other make it seem to sparse? Also, how would you outline the bed on the left (include the birch tree or leave it on its own)?

I can only respond to what you show and the first set of pictures reveal no detail of the foundation planting areas. Seeing it here, there's no question that I'd fill the space under the overhang with concrete, as an extension of the stoop. It's not a place conducive to growing any plants. 99.99% of the time, the stoop is created as such by the builder. I would not separate the stoop from the lawn (which is a wide, "carpeted" path) with a planting barricade. A direct connection between the two is a much friendlier look.

You can't make a welcoming approach to the entrance by pinching it off, which the walkway and the plant containers do. There are several problems created by the poor design of the walk, another one being that it is too close to the house, limiting having a genuinely nice foundation planting. You must redo it or accept the limitation.

I don't understand your question about the area you say two pipes are sticking up. You must SHOW it and include enough space around it so that the context can be understood.

Before you buy replacement plants, perhaps you'd like to look at Lois Hole's books on trees and shrubs. She gardened on the prairies in Canada, so her selections should be hardy enough to survive your winters, too.