Abe, what is the diameter of your nylon...
rode? As long as it is in good condition and the right size for your boat, not to worry about it breaking IMHO. Also, what size of chain, 5/16th? And grade proof coil, BBB, high test (grade 40), grade 70? Unless you anchor in coral where abrasion would become an issue, my choice is the 200 feet of nylon connected to the 75 feet of chain that you have.We always use a kellet at the shackle that joins the rode to the chain to help with catinary. As far as your question about weight in the bow, that again depends on your intended anchorages and the scope you want to achieve to meet the expected conditions.If you really want all chain then I recommend that you consider grade 70 in a smaller size chain to help reduce the overall weight but still retain the strength. In doing so, if you have a windlass, you will need to convert it to handle the smaller links. You may have some difficulty finding a supplier that can get you galvanized grade 70.Terry