Any other apps out there with intelligent 3D drawing tools similar to how Sketchup works but that won't cause all the frustration that Sketchup does?

I'm tempted to say that Google have made the program worse than I remember it prior to their acquisition. But I didn't have enough experience with it back then to make that concrete assertion. I will say that Google have continued to prove time and time again that they don't really know how to design a UI. Another painful example, which after all these years of development, you'd think would have made at least some minor changes to vastly improve working with it.

You want something that is like Sketchup but not Sketchup but won't say exactly what you don't like about Sketchup?

The core UI stinks. Not the drawing/modeling system, but the app UI. The viewport doesn't scroll when you're using most tools and push to the edge of the window. The fact that I said "most" is telling. It works with some but not others - inconsistency is a huge problem in this app.

Are there shortcuts to temporarily toggle the selection tool? For instance, while in another tool, hold down a key to toggle the selection tool, release to continue with the primary tool. I also find that the tools for controlling your view (orbit and drag in particular) must be selected separately from the tools that actually manipulate the objects. I can get around some of this I suppose if using a mouse, since alternate buttons can toggle some of this functionality, but I'd really like to be able to use some keys.

Some tools perform selection when clicking on lines/faces and others require pre-selection using the selection tool. Inconsistency again.

The layering system and locking system is a pain in the ass. If I put something on another layer it's because I don't want it to stick to something I've put on another layer. The automatic stickiness of lines and shapes to existing objects/entities can become a real pain sometimes. This one is a combination of app UI and functional design I suppose.

There's also a serious lack of 2D primitive tools. The triangle/poly tool doesn't allow non equilateral shapes. No oval tool. No rounded rectangles. There are no 3D shape/object tools at all, so you can't make spheres easily - the common recommendation is to import a sphere.

The paint bucket coloring and texture fill tool UI really really sucks. Inconsistent treatment of texture rendering size (sometimes retargeting the size works and sometimes it doesn't).

It's very simple to work with its constructs of push/pull to create objects, but I haven't found a simple way to cut or merge objects/entities once they've been fully developed. I'd like to see easy segmentation abilities similar to a 3D implementation of Illustrator's path finder.

My requirements are pretty basic, and I certainly am not an expert with the tool, but it's a huge struggle to overcome so many aspects of the UI that could have been implemented just a little bit differently to make them so much better. My sentiments seem to be expressed all over the place. The tutorial videos are pretty good, but only get you so far. Not everything can be put together the way the tutorials are structured.

Did I really have to write all this to get some suggestions on some programs that may offer a similar somewhat intuitive modeling paradigm? I didn't think so, since the choice should be somewhat limited, so many programs instead offering the classic 3-way view. I'm interested in a program for mocking up quick designs, laying out rooms, designing furniture, etc. Not looking for something like Maya nor 3D Studio Max.

I have no experience with anything that I could say is terribly similar to SketchUp, but here's a list of alternatives to SketchUp.

Thanks for the link Bitt. Unfortunately, none of the listed programs is an alternative, but it did help me find at least one other program I can use along side Sketchup.

Live Interior 3D from BeLight is a nice little app I had seen a couple of years ago. It's matured quite a bit since then and seems to be the perfect tool for working on building interiors. A lot more streamlined than Sketchup for this task since it's the program's specialty. That allows me to use Sketchup to work on individual objects, including potentially some exterior scenes, rather than complex interiors or other scenes requiring multiple complex objects.

Most of the apps listed, including the number one "alternative" were more traditional 3D modeling apps for creating poly-based characters and organic objects. The biggest advantage Sketchup has over everything else is that it's a sort of hybrid 3D CAD and illustration tool with a foundation in real-world metrics and scale. It just needs tweaks to make the creation of certain shapes easier and more intuitive. And of course the tweak I mentioned to help navigate the UI and objects.