Sketchup is actually very intuitive. It may even be its USP. The people who have most difficulty are those who (like me) have transferred from another CAD discipline, especially if it was 2D.
There are lots of good books and tutorials online and the Sketchup help pages are also a valuable resource.
I would say that whereas the learning curve of most CAD packages is steep at first and then levels off, for Sketchup it is quite gentle at first and then gets steeper. Above all, you must remember that it is a surface modeller and that you have to keep grouping discrete things as you go.
Moving things and changing their size is actually a doddle.
I am trying to convince my boss to use Revit, that is the program we have been using for 2 years at university.
You are correct about the grouping stuff, though i find it very difficult, allmost everything i am trying to move, pull or so on i affecting somerwhere else on the model. One of the best things in Revit is when i have a dimension on somthing i just retype the dimension and the part is moving exactly on point, or i just allign to somthing else if something fits in that direction.
The callout part i am missing aswell, i think it would be a good investment compared to the time i am using just to a simple model. In this example my task is to show the steel in the concrete slab, where it’s exacly should be on dimensions. And then finishing with a detail drawing of the position of steel in corners and so.
Now in SketchUp 2020 or the updated web versions it’s remarkably easier to move objects (groups and components) around and into position. Objects have far more logical points (on their bounding box) to grab them and align them with other geometry.
Also create objects with a logically located local origin.
Wanted to like your OP with +2 but that’s not An options.
Yes, that is both a strength and weakness. If you don’t follow the basic principle of Make, Group, Move On, you will come unstuck. Or rather, stay stuck in fact.
Let’s say you’ve made a simple box (Rectangle plus Push/Pull). Now you want to elongate it. Just apply Push/Pull to the relevant face. Then Group or Make Component. You decide you want to change something. Simple, you just double click on the Group you’ve made and edit in the usual way.
I suspect most people coming from other CAD software start by ignoring the grouping and just draw as they would before, except this time in 3D. If you are really (REALLY) careful, you can still get quite a long way without problem. But sooner or later, you will inadvertently move something you didn’t mean to (that maybe wasn’t even visible on screen) and you will be in a world of pain. By then, it will be extremely difficult to create the groups you should have started with.
All the things you ask about are very simple and quick in SketchUp, once you learn some core concepts. Those core concepts are unlike other programs. It can save a lot of frustration to start off on the right foot by learning the basics with a beginners mind, and not to try to bring in previous knowledge from other programs.
It has a great way of building stacked objects (and a lot more) - for instance a concrete slab with reinforcements and what I’ve could tell from the learning videos you will be able to change a lot of the placement by typing which would help you a great deal with your main problem of aligning and so on.
DK: It may be helpful to clarify your goals. The Sketchup / Layout programs are powerful tools to design in 3D and present in 2D, but to really get up an running requires a significant investment of time and effort. I have been using them for many years and still struggle every now and then with some feature or another. Sketchup Pro is relatively inexpensive. I have a Classic license I bought years ago, and annual maintenance is $120. Revit is powerful, demanding to learn, and expensive (about $2400/ year). In my experience the Revit users who become very competent use Reviit all day long every day. If your task is to prepare simple concrete slab construction documents, perhaps a simple and free 2D CAD program is the answer. The foundation and slab drawings I get from my structural engineer are remarkable works of graphic simplicity and clarity, all in 2D. To see if Sketchup is for you, I suggest setting aside a weekend and really digging in. As noted above, there are rich resources on the Sketchup website and in Youtube. Matt Donley’s videos and book are very good, and to see what a true SU/LO master can do check out the Nick Sonder videos. But first, learn the foundational Sketchup concepts. All is lost if you do not do that.