I had podocarpus at the fence of my old backyard. In 10 years they grow to 25 feet and are a trimming nightmare. But if they are in an area you don't care about then yes they produce privacy.

I have been researching the same - how to disguise the wall. It will be a fun project. As of now, I'm leaning toward the Sky Pencil Holly. It only grows 6-8' tall and 2-3' wide (our back strip of yard between the lanai and wall is not very wide). There are similar taller columinar varieties, but in the long run, I don't want the maintenance. I plan to plant them a few feet apart and then plant something flowery in between each (in a row in front of..) that attracts hummingbirds or butterflies. Then, I will make a slight wavy border with some decorative edging along the back length of our back wall and fill it with rock or tire mulch. Also, in one corner I will have the edging come out a bit further to include a bird bath. I will check with the arch approvals. If not approved, I'll just use large planters, versus planning in the ground (not preferred, but..)

If your crotons get hit with frost, leave them alone until mid-March or so (last chance of frost). In March, look at the main stem. The top of the stem will be brown and the healthy, green stem will be towards the bottom. Just cut off the brown part of the stem and the plant will regrow nicely.

No need to wack the plant down to the ground.

If in doubt-cover. Just did mine incl 4 crotons. Geez. It was cold out there with the wind etc. despite the nice sun.

We had 3 large crotons in pots on the lanai and they got so big they needed to be put in the ground, which we did. The first year they were in the ground they froze, about four years ago. Now we have three more in pots and they are happy to have been moved indoors for this cold spell.

Otherwise, they give a lot of joy and color for little trouble. Don't seem to be bothered by pests. When they are thirsty, the leaves droop but perk up shortly when they are watered.

Viburnum is actually a group of plants. We have whatever Viburnum whatever variety that was put in by the builder and they are roughly 9 years old. They are tough as nails. I cut them about every month or two. I used to do it with hand shears. A quality electric one or gas if you watch too much tool time, is faster and easier. We have them on the north side, south side and west side of our home and they all do fine.

I have several Hawaiian ti plants and they have been severely damaged during the winter freeze. BUT, I cut the freeze dead off of them and now they are thicker and more beautiful than ever. Almost everything I have that has been damaged by the cold have come back and anything that hasn't come back was easy to replace. I don't bother covering anything.