I think any system is flawed as there will always be someone who finds a way work the system. It is the same for CSA and same for benefits system, same even for family courts system.
There are ex's on both sides that either do not go for the contact they should and those who try to limit contact of NRP. You only have to read this thread to see that there are to many people on boths sides - which in itself proves that the system rarely works for anyone.
It is unrealistic to say that contact and finances are a completely separate issue. Whilst I agree that children are not and should never be pay per view, the level of the contact will determine how much should be paid - this allows some RP the ability to want to restrict overnight access as they would be entitled to less money.
My ex only paid £3.75 per week as he had another daughter that he paid £65 per week to. He genuinely did not know of DD existence until AFTER I had given birth and her mom said she heard he had had another child and thought that may or may not be my childs brother. She had not said anything about it may be his daughter in past because she was not sure who dad was.
If my DH was not financially able to help support both me and DS then who would have - should I have just packed in work and stayed single as well as claim benefits?
Now my DH pays through CSA (because his ex was on IS when they split so there was no option to arrange private payments) but at the time she refused any overnight access and so CSA payment was based on this and still is. Yet we now have EW access and half holidays. CSA has never reviewed it and DH won't ask for review as he knows despite contact order ex will drag us back through courts AGAIN and whilst it would not stop contact it would be an expensive point roving exercise.
If my ex was forced to pay equal to DS and his DD then it would have been fine.
DH's ex was given 3 bed council house and got to be SAHM because DH supported the children and the government supported her.
DSC had laptop given to the household for the DSC because they were classed as on poverty line due to benefits but that was more than what we could have afforded for DS.
If DH lost his job I would still try an support DSC not because DH ex would expect it - even though she would but because I love them kids and would want to do everything that I could to support them.
If I was out of work I would expect my DH to want to support me and also my DS because he loves us.