Part of maturing is resisting the urge. The urge to say the first thing that comes into ones mind, the urge to say the second thing that comes into ones mind and the urge to say anything at all.
If you do not like your project, remember this, and do it differently when it is your turn to arrange things. My experience is, you will with high probability suddenly discover how difficult it is to get things right while balancing every other constraint around it. You do not know why they designed the project the way they did. You talk about 200+ course participants? Perhaps they simply do not have the manpower to manage each of you individually, who knows?
Also, I find it remarkable that a comparatively minor criticism (such as the style of a problem-solving session, compared to - say - bullying, intimidation and the like) so much more often elicits the urge in people to write "strongly worded" responses. If people stood up to the system earlier in serious violations, who knows, perhaps we would not be where we are?
Maybe you are right in your criticism. Maybe not. We cannot judge. But you should think very carefully what you wish as outcome from expressing this criticism. If it is just venting and making your point, I recommend to drop it.
If it is that you really wish to improve things for future generations, and that's what you sacrifice your own well-being for (namely your letter of recommendation), that is your decision - in this case, the "strongly worded" part is counterproductive. You will neither get a fantastic LOR (unless the teacher is a saint) nor help future generations. The best in this case is a factual, but not charged list of suggestions for improvements. Best is you concentrate on the really important ones rather than a long list of "could be improved" entries.
Finally, keep in mind the possibility that you have not seen the whole context under which this project has been run and your teacher actually knows what they are doing.
Sometimes (and we, your internet advisers, cannot ultimately judge whether this is the case here) not saying anything is the best thing to do.