No, it may not be necessary to use every suggestion made by the critic. If time is a factor, one strategy is to try implementing just a few of the tips at first. Dependent upon the engine and term you are targeting, it is possible the page will achieve a good rank based upon just a few of the Critic's suggestions.
However, if the page in question does not achieve the rank you wish, implement a few more tips, upload, and submit again. You can expand out and make use of more of the recommendations as necessary.
For engines that take weeks to index, you may want to implement most of the suggestions the first time, to give you the best chance of ranking well the first time around.