A method for overcoming a problem or limitation in a program or system.
Evernote is still a workaround even on a desktop or a laptop because Evernote itself not a native feature of operating system, it is actually a method for overcoming a problem or limitation of the operating system.
That's really a stretch, and it doesn't even meet your own definition.
Most of all, it doesn't really address the main point.
By choosing an iPad you are imposing on yourself problems and constraints that you would not have with a MBA.
Choose the right tool for the job.
The iPad is a great device for viewing and reading. That's what I use it mostly for.
It is not so great for composing, particularly long, complex documents that need a variety of graphics, tables, etc.
It works OK for light typing of plain text, but not so much for moderate-heavy typing of rich text with complicated formats (numbered/bullet lists).