This is what I have done the last several seasons, I mostly use a .58 as I have not hunted Turkeys or waterfowl, I do have a .62 smoothrifle should I need a bigger gun, if I were hunting the larger birds on a regular basis I think I would go with the .69 cal, this still gives a good Deer/ Elk gun without having to use a bowling ball for ammo,I have found the smoothbore to be quite adequate out to 50 yds with ball and a fairly snug choke pattern can be achieved with load tweaking as many have testified to on this forum, others are much more experienced with this than I am, I would make a list of all the game you hunt, the ranges you feel will be in play for big game and for fowling and small critters and build the gun around what bore size is needed to cover all the bases,you may have some weak spots (pass shooting Honkers at 50 yds or 150 yd shots at Deer/Elk) that a ML will not be the best weapon to use but overall you should find a smoothie bore size that will suffice, then it is a matter a builder, what style you prefer and handles to your satisfaction.Many choose the .62 and live with its occasional limitations, this may be something that will work in your situation, there are a lot of .62s available and the components are easily had as well and there are a lot of people with load data to share from Deer to Turkey and likley beyound, the fit is the key, just like finding a shotgun for serious competition.Good luck and enjoy the journey. Smoothbores have a way of getting under your skin in a good way :thumbsup: