That may well be true but he has a relative large amount of freedom at Burnley so how likely is he to want to come to Palace where the manager doesn't have much freedom in the purchase or sale of players and he will effectively just be a coach

Looking at the way he now has Burnley playing. I would think he would take a lot of convincing to make what at best would be a side ways move.
It been a lot of hard work getting The style Burnley now begin to show, it not finished, by a long way , but considering all we know about Burnley, it is all is going the right way. The fact that Burnley are still behind us in the table shows how difficult any sort of survival in this league is.
Dyche, would be a decent choice, but I think there has to be two clear doubts, one I have said , the other would the board give him tools clearly better than those he has at Burnley?

A lot of Dyche chat. Whilst agree he would be ideal replacement, there’s hardly a carrot for him to make a sideways move to Palace.

Howe or Wilder would be the more obvious/likely options.

If that's the case then he'd most definitely not want to arrive, we saw wonderfully how his side managed to get at us during both games this season although the one at their place was during their poor moments and we were horrendously wasteful in the good positions we found ourselves due to our inabilities, his squad although not as a whole technically as good as some of the higher sides has something our squad has nothing of which is tenaciousness and this comes from the players not the manager, he has created this in bucketful's over a long period at Burnley and for him to come to us he'd need good funds and ability to go for who he wants within our finances ..Townsend for us is at the moment showing us the most in this department.
Burnley have improved their possibilities though haven't they recently so I doubt very much he'd even look at us.

I think ambitious Managers want to see opportunities to develop and and grow a club. Both exist at Palace and we have the nucleus of a decent squad - with a plan to develop the academy and feed the first team and expand the stadium (if Sainsbury’s ever play ball).
Where the club has fallen short under Roy is investment in the squad. But they haven’t needed to have they - he kept us up without significant transfers and has provided the stability hoped for - ready to embark on the next phase with our powder dry.

We are due a new cycle of investment in players and I hope as part of SP’s planning for the next 5 years that will start as soon as this season ends with the new Manager influencing the signings we make.
Maybe the prospect of a longer term project (and a contract to reflect this), coupled with the potential growth of the club and significant investment in the squad, would be enough to lure a manager the calibre of Dyche , Howe or Wilder.

You make a very good point, Roy has done a wonderful job for this club over the last four plus years and has been a great revenue generator by keeping us in PL. He has put up with a lot of criticism and he has not been supported in the transfer market and yet he has not walked away, like others did before him. Why would any decent Manager want to take on such a high risk job due to the aged squad and at least 12 squad members out of contract this summer and then in all probability he would likely only be given a very modest transfer budget. As they say better the devil you know!