Need some workflow tips for 2D point & click games

Greetings developers!

I'm working with two friends on 2D game in Unity.
They had no previous "touch" with Unity and I didn't work on 2D game or with 2D tools in Unity.

Could you please help us out and write some answers or tips for general workflow?

- Limiting movement and faking 3D :

We have scenes that look 3D but are of course 2D painted images.
We need to limit movement of character and fake that 3D feeling.

What I'm doing now is using edge collider to create walkable paths/regions inside the scenes, so that character can't pass where it's not supposed to.
This looks like this at test scene that is not related to project :​

And it works good, however I don't fancy using physics to move character in such simple game, so I rather use Vector2.MoveForward to move the sprite. This of course gives bad results at huge speeds, but since our char is not going to reach those speeds ever, can we use this system to limit movement ?

Or is there other practice for limiting movement that you use?

- Pathfinding

I figured out that I could probably create few waypoints and create my own system for moving between points. I was considering casting a line from sprite position to click position, and in case that there is an "invisble wall" on that path I would cast another one from closest waypoint that sprite can walk to etc. Something based on casting idea.​

Is there already some better solution for this ? I don't expect our scenes to be that complex when it comes to movement so I assume that writing own waypoint system wouldn't be problem. But then again, maybe there is general workflow practice for creating both pathfinding and movement from something else.

General Workflow:

We set up some base guidelines. Our scenes will always be 1080p, but artist will create them in much larger resolutions (2 or 4 times that) then downscale them to 1080p for import. We will use letterboxing and always show whole screen to player. We got most of that done actually, including spritesheet, animations and letterboxing, from small study of other adventure games and their behavior. ​

But any tip regarding workflow or answer to any of questions will be of great help.
We can't really afford paid assets, because we're not studio but rather three people that want to create something, (we're also using Unity Free) so only free suggestions or tools that could help us are considerable.

Thank you so much for sparing time to read