The sugar/molasses is beneficial to the living soil method of growing, but unless you are using this process, it won't help. As was mentioned, a LOT of light is essential for getting big buds... you need a lot of energy to let them swell up, which they usually do at the last few weeks of flowering. If you want thick, sticky buds, you have to provide the proper genetics as well as the proper conditions. A Sativa plant will give you longer and less dense buds, while Indica strains tend to have the round, hard nuggets that everyone seems to desire.
If it was up to me... I would buy a 600w MH conversion bulb, so that you could veg under MH's superior spectrum, and swap it out for a 600w HPS during flowering, which you already have by the looks of it. I use
Promix and 5-6 gallon buckets, but whatever works best for you.... use it. The Rh is a little high, but it shouldn't really affect things too much. Lastly, find some strains that are well known for having the qualities you like...gooey, smelly, nuggets... it's all out there anymore. It used to be that you grew whatever you could get, but times have changed. You seem to be doing OK currently, it is just going to take some upgrades and the other very important ingredient. It is free but worth more than a site's worth of info... and that is patience! Newer growers can't wait for their crops to come in... who could? I "allow" myself to pick one smaller bud a little early, just to keep from driving myself crazy with anticipation. Keep up the good work... keep us in the loop!