I've found LTspice ("Linear's switcherCAD" as mentioned earlier) useful although in general I would appreciate if these circuit diagram creator solutions would offer more high level abstractions such that one can be more productive.

 

They have free software like Linear's switcherCAD (www.linear.com). I believe you can draw circuits on there, and then you can just take a screenshot (hit printscreen), and then go to paint and you can paste your screenshot and save it as a jpeg (don't save as bmp they take up a lot of space).

With LTspice (switcherCAD), just copy the window to the clipboard (ctrl-c), paste into Microsoft Paint, and save as .png (fewer artifacts and usually smaller file size that .jpg).

 

I've found LTspice ("Linear's switcherCAD" as mentioned earlier) useful although in general I would appreciate if these circuit diagram creator solutions would offer more high level abstractions such that one can be more productive.

LTspice is a simulation program. Schematic drawing tools are provided so one can easily generate netlists for simulation. It is not intended to be a high-level graphics program, with menu-selectable block drawing symbols, etc. You can use it that way, but you have to create your own symbols, etc.