I always find that an advertisement or a single website does not satisfy everyone who looks at it no matter how much time and money is invested in it. There is always room for improvement with any form of media, but every site you look at, blows their own trumpet and professes they are the best at what they do. But non of them give you a good reason why you should use their services, and not one the other side of town?
I have just set up on my own again only last November, and in a previous life a few years back, I advertised with Y.P. and T.L with a half page advert; and had a free phone number, I didn't have a website. And most of the enquiries were time wasters, sales calls, or folk wanting work doing or attending to emergencies, but more concerned with the cost and wanting a breakdown of it, rather than safety, service quality, and guarantee.
You have listed everthing that you offer as a service to the public, but the part about old fuse boxes with no rcd protection does seem to be on the scare mongering side. But that's coming from another trades man who knows that they are not always desirable in most cases these days. But don't need changing just because the regulations are always changing, but its a complex task explaining it to customers.
I also find that blogging and testomonials from customers is questionable, as I onced used the services of a roofer with a snazzy website, as nobody kne of one who were going to be quiet for at least 6 months. They in turn had customer testimonials on their site. He re roofed a house I used to have, I paid him and afterwards it leaked, but the old one didn't, I just got it done out of peice of mind because it was over 100 year old. He couldn't sort it out for some reason, then he went out of business leaving me high and dry, or wet as the case was. But he had no where on his site for unsatisified testomonials from customers, or he had deleted them. I have spoke to folk since who were also his victims or knew of someone who was a victim. I am in no way suggesting that is what your doing, I'm just speaking from experience.
Anyway all the best with it and I'm sure it will attract enquiries, hopefully more from folk wanting to give you business, and not folk wanting your business.