This may sound a little abrupt but, if you are afraid of competition then you probably shouldn’t be in business. The hidden gem concept is about finding work arounds to the competition for high volume keywords. The idea of the hidden gem is to find keywords with low to moderate competition with decent search volume. This may have some merit for global search but for local searcgh engine optimization they are not useful.
As a local business your geographic search area is already limited. You will only be able to benefit from a fraction of the global searches for a keyword as it is. A local business needs high volume, high conversion rate core keywords.
What is the value of a hidden gem to a local business. Even if you can by pass the competition by using a clever phrase to get site visitors will this pay off? Is your goal to increase web site visits or sales? Hidden gems may not produce a good conversion rate.
In a way, the local SEO hidden gem is the core keyword paired with geo-modifiers. Most local businesses aren’t using geo modifiers in their Meta Keyword list. They are not optimizing for them. And geo-modified keywords tend to have a very good conversion rate.