There were Royalists now who were not Stuartists, who wanted a king on grounds of general principle and expediency, but were not resolute that he should be Charles II.only.The real combination of elements against Oliver's Kingship consisted, therefore, of the unyielding old Royalists of the Stuart adhesion, regarding the elevation of the usurping "brewer" to the throne as abomination upon abomination, the Army Oliverians or Lambert and Fleetwood men, interested in the preservation of the existing Protectorate, and the passionate Republicans and Levellers, who had not yet condoned even the Protectorate, and whom the prospect of King and House of Lords over again, with all their belongings, made positively frantic.
How far Cromwell had been aware beforehand of such a project as that of Sir Christopher Pack's paper may be a question.

That he had let it be known for some time that he was not disinclined to a revision and enlargement of the constitution of the original Protectorate may be fairly assumed; but that he had concocted Pack's project and arranged for bringing it on (which is Ludlow's representation, and, of course, that of all the Histories) is very unlikely.

The project, as in Pack's paper, and as agreed upon by Whitlocke, Glynne, and other lawyers and Parliament men, was by no means, in all its parts, such a project as Cromwell himself would have originated.

To the Kingship he may have had no objection, and we have his own word afterwards that he favoured the idea of a Second House of Parliament; but there were accompanying provisions not so satisfactory.

What he had hitherto valued in his Protectorate was the place and scope given to his own supreme personality, his power to judge what was best and to carry it through as he could, unhampered by those popular suffrages and Parliamentary checks and privileges which he held to be mere euphemisms for ruin and mutual throat-cutting all through the British Islands in their then state of distraction; and it must therefore have been a serious consideration with him how far, in the public interests, or for his own comfort, he could put himself in new shackles for the mere name of King.