Great post. I would also say:
1) don't get caught up in any one name
2) having too descriptive of a name can be disastrous as you won't have as much flexibility
3) have fun with it!
Some speakers can get away with it, whether as a form of humor or setting completely unreal expectations (ie. I am not prepared, but then blows the audience away with their knowledge).
Normal people can't do it (which most certainly includes myself!)
A great way to find which one to focus on is:
1) Ask yourself which would be more fun for you to do?
2) Chat with the people that could use whatever you are building to get their thoughts (but be sure to talk to people who you don't know, as "only positive feedback" will give you the wrong conclusion.
3) Rate each project on an easy to hard scale and then weight them against 1 & 2 above.
Not only that, but vertical has a better chance of even making it past the short-term. With a vertical, it's much easier to find a pain point that needs to be solved, build it, and focus your marketing efforts.