Refurbishment of a 20 year old pool

[Thedeanmanning]

Hi. I am new on here so please be gentle.
I have an in ground, outdoor swimming pool that is 24'x12' in size. As the pics show it has a deep end that slopes in from all sides to a 3' square that is just over 6' in depth.
My issue is maintenance. I have already replaced the liner once and I wanted something a little more permanent than to change it every 10 years. Being in the UK we only get 4 months use a year so in the winter months I would like it to be easier to maintain.
At this time all of the leaves and dirt collect in the bottom square of the deep end and all along the creases of each slope. To make it easier to maintain and for the safety of my grandchildren I have decided that I would like to make the pool all one level... The same as the shallow end which is 4' deep.
My questions are:-
Would I simply be able to fill the deep part with rubble etc then eventually just concrete over the top until it is smooth and level?
Is there any other way of doing the refurbishment?
Any other suggestions?
I have read the article on painting the pool and as an effective cost saving measure it seems the way to go?
Do I need specialist concrete?

Please note I removed the liner 3 weeks ago

 

[JasonLion]

If you are going to use a vinyl liner, then filling in the deep end is fairly easy. The main consideration is to either use stuff that compacts really well, or let it settle for most of a year. If you are going to use something other than vinyl, you need to make sure that the final concrete surface is solid and the new and old sections are well connected to each other. That usually means drilling holes in the existing concrete and putting in rebar that will connect to the new concrete, and using a much thicker layer of concrete than you would use with a vinyl liner.

I strongly recommend against paint. Painted surfaces almost invariably require repainting every two or three years, regardless of claims made by the paint company.

 

[Thedeanmanning]

Thank you for your prompt reply. Concrete followed by a vinyl liner seems the easiest option. At least the liner will be cheaper because there will be a lot less of it.

 

[Thedeanmanning]

If I were to paint it, are you saying that because it has always been a vinyl pool, the concrete too thin?