As a 30 year in the insurance business will tell you to trust the agent, but not all agents. If you can not trust the agent to know the law and the product then you are not talking to the right agent. I always tell people ask them to point to it in the contract and if they can not then find another agent. They are out there. Realize if the agent is doing a good job for you they are spending a good bit of their time on this and let them know you will be loyal for that IF what they bring meets the needs. Too many people will ask for quotes and never ever respond. If the agent knows you are serious you normally get a better job. Same as you do in quoting jobs.
But insurance laws do vary from state to state. One thing each state should have is on their state Dept of Ins web site list of complaints against any company and how they turned out. Some or dumb complaints and some are really valid but gives a good review. At least my DOI will go into detail with you on those IF YOU WALK into their office but not on the phone. No idea why. Your DOI may have history of rate increase which will give you idea on stability of their rates.
On vehicle insurance talk with body shops and get their feed back. They work with them. You may find a shop who only works on a brand or two's claims but ask them.
Do go to the company's web site and some are very helpful and some will have you so confused your head is swimming. People who do the web sites are not always insurance educated.
As other people who they use in the construction business.
One thing to remember companies are being bought and merging all the time and ole so and so company by what ever name today may have nothing about them that resembles their company name of say even 5 years ago.
Do ask what their financial rating and then ask what is the best and worst grade that rating service gives. You do want a company who can afford to pay the claim.
Now back to not trusting an agent, to me your agent/agency failed you greatly if what you said happened is what happened. They got notice of the failure to pay and with the size of your premium it made business sense for them to want to keep your business and why in the world they did not call you to warn you is beyond smart. It is dumb. Such as that in one reason I strongly suggest you have a local agent over going to a web site or toil free number is the agent should be bringing you education on options, products and company and coverage needed and not needed and then the service. Never heard of a home office doing more than mailing a late notice and then termination notice to an insured while many times the local agent picks up the phone and calls the insured or the company to prevent such or to get it taken care of quickly.
Really sorry for your problem there. One suggestion, if you really decide to go direct to the insurance company call their customer service line (go to their web site and find it do not ask the sales side for it) and see how long the hold time is. Today I was on hold with a customer service number for about an hour waiting to make request for one of my insureds. Still ended up having to leave message on what was needed and if they honor the message all will be fine but if not I do log such calls and they normally have recorded lines on such to prove what the message was. I have the luxury of putting phone on speaker and go ahead with other work and for a guy in the filed that is not a real option. Now in all this there are some companies who only sell direct that do a good job.
As to the idea on your son some companies with place him on the highest price vehicle the house hold owns regards of what you say while others will allow you to buy a clunker and put it as his primary vehicle. Just have to ask.