Tartan 31 or Pearson 31-2
I have sailed out of Racine, WI for 25 years and have cruised the lake to virtually every port. Either boat would be fine for the lake. With low water levels the 4 foot draft will be a nice thing to have. I draw 5 and have found the bottom a few times. If you don''t run aground once in while, your not being adventerous enough.
Quality wise - the Tarten is unquestionably superior. Pearsons are designed as coastal cruisers - Tartens are built to go offshore. I would not hesitate to take either boat anywhere on the lake. I would also feel confident that either boat would perform well for you in L Michigan conditions. One thing about the lake, is you will never be more than 8 hours from a harbor. It is not like you will make a 5 day passage.
Both boats seem to resell OK in the area. Tartens are usually more expensive - but they are built better.
Both manufactures have boats dating back to the early 70''s still sailing. Pearsons, of course, go back to the 60s. Not sure about Tarten.
Me - I would prefer the Tarten because of its reputation for s1st class quality.
One thing I would look carefully at is the rudder. I have seen boats with a rudder that draws more than the keel - not good when you run aground and if you cruise a lot it will probably happen unless you are VERY careful.