State Pension Age Conundrum

The state pension age is currently set at 67 and there are plans to rise it to 68 and even 69 but the Government are pondering aloud on at some point maybe thinking about possibly lowering it instead.
Very much a kite flying exercise where they mention something in passing and see how it lands with the public and if it gets a bad reaction, they can just say it wasn't actually a thing and forget about it but the idea of putting your feet up a few years earlier than thought seems to be quite popular so they may ponder on it a bit harder.
I have never been able to sort out in my head if the pension age should go up or down, up means less pensions to pay out because in all honestly there are fewer 67 year olds than there are 65 year olds and being dead is a handicap when it comes to claiming your old age pension which saves the Government money but by people staying in employment longer it creates a bottleneck with less jobs for the new generation as the oldies roll on.
Of course by retiring people earlier opening up more jobs, the Government will save on Unemployment Benefit so i guess it comes down to will it cost them more to pay out Pensions earlier than they will save by not paying out Unemployment Benefit and if not, would seem a bit of a economically backwards move. 
There are some ways that I can think of which might work as you presently need 35 qualifying years of National Insurance (NI) contributions or credits to get the full UK State Pension so one option could be you are entitled to retire once you have reached the threshold because working beyond that isn't going to earn you anymore and I can see how that would be popular, even putting it up to 45 years would mean if you began work at 16 you would be clear and eating Wurthers Originals by 61.
As it is only at the 'Hmm....maybe we could' stage there are no plans for what they are thinking or the age they want to lower it to but i'm still unsure if it is a good thing or not, but by making it you can take it earlier if you have the qualifying years if you want to, it seems a happy halfway between what we have now and what most people seem to want.