Hi Dragonflye
I find that the less I weigh, the less insulin I need and vice versa if I eat more and gain weight, the more insulin.
Regarding Lucozade..... I bought litres of the stuff when I first started pumping and it was starting to burn a hole in my bank balance so I stopped and sought full sugar ginger beer (supermarket own brand for cheapness) and found it contained more sugar per 100ml than Lucozade and was considerably less expensive.
Nowadays,,,, I keep sweets and a biscuit on me when out and when indoors I just use 2tsp of sugar in a warm/hot cuppa coffee or tea.... Works more or less the same as Lucozade. Occasionally...... I'll still use some chocolate as that works well even with the so called fat in it.
Have you tried using a TBR for the hours that you find yourself going low and done a bit of 'trial and error' in finding out what will work...?