Glad to see that you're making some progress in learning Atom3D.
I looked at your models and I'll just point out a couple of things: It is best to investigate and correct any modeling errors before moving on to the next feature. )Errors show as
RED features in the Design Explorer.) It appears that you recreated the Fillet in your "Interesting design loft". IF you RMB click on the feature then select Status from the pop up menu it will let let you know what the issue is. Be aware that some of the "messages" in the Status dialog are cryptic at best and can only be interpreted by a programmer. But sometimes they make sense and it is possible to correct the issue.
IF a feature fails, like the fillets, check the status and repair instead of just reapplying the same feature. Fillet<19> failed because the radius is too large. It looks like you just reapplied the fillet with different radius values instead of editing and reducing the radius of the first one that failed.
You can also create a Loft CUT if a shell fails or you need a different profile that what a shell would give you. I deleted all the Extrude Cuts and used their sketches to create a Loft Cut. That may give you a better inside shape than using Extrude Cuts and fillets.
For your "Cool funnel" I would either fillet the outside corners before the shell or at least before filleting the bottom. IF you fillet the inside after the shell reduce the radius by the shell thickness in order for them to not fail.
One last point on terminology, it is better to use correct terms when asking for help so everyone understands what it is that you want. When working in a 3D workspace you are creating a part
model made up of
features not a drawing. A drawing is a 2D representation of the 3D part or assembly.