DON'T KNOW WHO YOU'RE HIRING & DODGY INSURANCE-GOOD DEAL THO

Via Carrentals.co.uk i have a booking with rentalscars.com. With their 'insurance' the deal is £365 for 18 days. (272.00 without insurance) so a good deal. BUT...
I do not like the insurance set up on this site and others. These 3rd party hijackers they use. The insurance side of things has changed this year. Before, you were usually offered insurance from the car hire company itself and they always offered a chance to pay a higher insurance eliminating the 'excess' altogether which i prefer but that wasn't offered today when i booked the car & for previous rentals this year as well. Why not? I am not happy with being 'reimbursed' after the incident because lets face it, insurance companies DON'T or try their very hardest NOT to reimburse causing loads of hassle and unecessary trouble and stress.
I want to rid myself of the 'fear' of anything happening to their oh so precious hub caps (which by the way seem to be deliberately made of softer more pliable material) or the paintwork. I drive around so tense and worried about other drivers bumping into me, parking miles from a kurb just in case i scratch the hubcaps. I park miles away in supermarket car parks to avoid other drivers just in case someone knocks the car while im not with it. I also find this type of insurance a nightmare especially if you collect your car in the UK or anywhere North after 4pm in the 'pitch black' and need flood lights to investigate every nook and granny before you drive off the forecourt and liable. (Stansted-green motion for example was ridiculous trying to check the car out last month as all public light near hilton hotel is extremely low wattage)) I feel forced into buying this type of insurance. is that an acceptable feeling in this day and age when is comes to sales and purchases?
On top of that my experience with some hire companies once i arrive to collect the car is they aren't too happy either that i have alternative insurance and automatically increase their excess. This happened to me 3 times at Dublin Airport, with tooleys, budgetcar and enterprise, they increased the excess to 1000 euros. for crying out loud! In these instances i had to accept the car hire insurance and then cancel the insurance offered on the net at the time of booking but i didnt have time to do this as i was in Ireland to work not sit around waiting for insurance companies to pick up the phone!
And also i wish to know who the hire car company is before i book the car, especially if i don't have free cancellation because i may want to cancel after i have found out who the company is. yes, in some instances you can see the car hire company (usualy the more expensive deals) but when the offer comes from 'hirecars.com or rentalcars,com or carhire 3000' who are affiliated with many companies then you don't know who you're dealing with until after you click the button and all the info arrives in the inbox. With my job over the years i have hired 100s of cars all over the world some good, some ok and some really bad experiences. The 'really bad' ones i do not wish to use ever again so it can be a real nuisance after i accepted the booking to find out its with an undesirable company in the end and i have to cancel it. Thankfully today's booking is not with one such company. BUT I now have to call the actual company/Avis to confirm what will happen regarding insurance when i collect the car next month. Sorry to go but these are real bugbears with me.