Grayson's men crashed out of the League One play-offs following a 2-1 aggregate defeat to Millwall on Thursday but the 39-year-old is determined to keep the nucleus of his squad together for next season unless he receives any "ridiculous offers".
He said: "I have sat down with the chairman over the last couple of weeks and we drew up plans based on whether we would be operating in the Championship or staying down next season.
"There are only three players not under contract and we don't need to sell anyone unless we get ridiculous offers - we would consider that I suppose.
"There will be a lot of hype about certain players leaving the club but I know the chairman is very reluctant to do anything like that.
"We will build on the group we have got and aim to win promotion outright next year by sticking together."