First thing I would say is if you are doing something that's already got a ton of recipes out there(like rum), start with one of the established recipes as your base and modify it from there. Use what works and tweak it to be your own. TAKE LOTS OF NOTES DURING THE PROCESS! I hear all the time from my brewing friends, man this is great, I just wish I could remember how I did the mash/ferment/boil. That is a "snowflake" brew, so unique you can't remake it.
If you are making a rum I think you need to worry less about nutrients and just concentrate on your ingredient volumes. Don't aim for a really high ABV and you'll be fine without nutrients. The molasses has enough nutrients in it to get you to a moderate ABV on its own. It's when you really start to push the limits of your yeasts ABV tolerance that you need to start controlling temps, using oxygenation, adding nutrients, and taking special care of the yeast so they have the best chance to achieve a high ABV.
Of course, it never hurts to add a small amount of nutrients to boost their ability and ensure a smooth ferment with as few off flavors as possible. Just make sure you don't overdo the nutrients because that will also cause off flavors. Google up "Staggered Nutrient Additions" and do some reading on that process, that will get you a good idea of a nice nutrient regimen. This is taking it to the extreme and most people will not want to take that much time to add nutrients 1-2 times a day for 3-4 days but you need to figure out what works for you and your ferment and go with that process as your own.
Everyone has different tastes and different ideas of what works best for them, that's what I feel is recipe development at its ultimate. Don’t be a snowflake! Don’t think you are going to create a gem on the first try, most likely you are going to need to brew several batches to perfect your own perfect recipe. Experiment, have fun, be safe, that’s what the hobby is all about. Don’t get put off if you create a few bad batches, we have all done it. A good part of recipe development is knowing how to brew, do a ton of reading.
MrDistiller > 2" potstill > copper 4" perf 4 plate flute
"I seal the lid with Silly Putty, that's OK ain't it ?"
"Attach a vibrator to it and hang it upside down. Let it work"