Carol your main problems in Mayflower are going to be tidal as I think you have found out, this is particularly so in the outer pontoons. What Johnny has said is very true for boats like ours long keel and heavy. Accept that you may have to reverse out all the way into clear water and dont try to turn her through the wind particularly if the tide is pushing you back towards the berth you have just come out of, you are likly to end up pinned against the downstream boats. Go out in reverse short bursts on the engine accept which way the boat is naturally going to turn and if it is stern first continue, you may well have to straighten her up a couple of times by going foreward which means that your exit will be in the form of a series of linked s's. Definitly check which way the prop kicks, do this in your berth tied up with the engine in astern when you will see which side the water flows and also be able to feel which way the boat is being pushed.

I would definitly counsel against going for it the consequenses don't bear thinking about, definitly think about the tide if possible wait untill the tide is weakening and with you for your first attempts so that you can motor back against it and turn through it.
Perhaps you shouldn't have left the yacht haven, less tide and more sheltered from the wind.

Good luck.