Right on point. You nicely summarized methods and process of antenna development
in an antenna engineering firm I worked for.
Use case, establish what you need the antenna to do. Also try to not succumb
to excess added features. The other side of that is no antenna need be forever,
so try different things to meet the need. That includes ways to easily to raise and
Design/build/evaluate/modify process is a well known engineering procedure
to developing a functional product. To that I add conceive and evaluate candidates
as that is where the process is process started. Its research, look at antennas and
try to understand what they can do in a specific case. Not all candidates pass
muster but one may be the diamond. Also failures can evolve to be the niche
solution rather than the general.
Simplicity, within the bounds of fitness for the design purpose.
Always keep in mind the goal. And if all else fails, KISS, then build it well.
All to often antennas are a target of magic thinking or outrageous claims.
Substance is measurable, construction quality, material quality, applicability
and frugality. The latter is not "is it cheap" but "is it a good value".