I do so love a good digger conversation.
Like Jewyl, I've got my fair share of luck. I've got two charaters 120+, with only enough dex to keep their weapon skills at their current level. The only real reason I've put those points into dex is because I sometimes get bored with digging. It lets me get mushrooms a little earlier than a pure-luck digger, but in the long run, when you get the mushrooms doesn't make much difference if you're just a digger. I think it's pretty obvious that putting EVERYTHING into luck (except those 6 character creation points which you can't) will maximize your digging profits.
If you ask me, overloading on the good stuff really isn't all that bad of a thing to happen, as long as you're in the habit of digging near to a store and a bank or market. If you're really into fine tuning your silvers/click ratio by limiting your number of trips to the store, you should probably look more closely at your discard strategy, rather than adding to your weight capacity.
Notice that only disprosium (10k/kg), oreputty (10k/kg), silver (10k/kg), gold nuggets (20k/kg), kithrill (20k/kg), centrolium, (33k/kg) hyperium (130k/kg) and diamonds (1m/kg) are worth equal to or more than their weight in silvers. Emeralds are the next best at 1750/kg, and they're not even close: it over 5.5kg of emeralds (142 of them) to add up to the value of 1kg of disprosiums (2)!
The recent Digger Study provides a perfect example which proves the effectiveness of this "worth it's weight in silvers" strategy. In the first block in the study, I made 1.65 million silvers (all sales at 50%) in 1000 clicks by throwing away only copper, iron and tin (weighing 2825kg and worth a mere 40k). Of that 1.65 million, a mere 66k was made up of emerald, ruby, pearl, lapis lazuli and opal (items NOT worth their wieght in silvers). These weighed an astonishing 123kg. So to make that 66k in silvers, I had to truck 123kg's worth of stuff to the store... that's almost two full loads for digger with an antiballast and no strength or persistance.
Compare that to the remaining 1.58 million in silvers that I got from the "worth their weight in silver" items. These weighed a mere 53kgs... which does not even require ONE trip to the store for that same digger.
Had I thrown away everything except the stuff that was worth more than it's weight in silver, I would have made 2 fewer trips to the store/bank/market by forgoing a mere 66k in profits... that's only 4%!
So how do you determine if it's worth it for YOU to throw away all this stuff too? Dig a full load (minus copper, iron and tin), calculate the 50% value of the "less than their weight in silver" items, divide that by the number of clicks it takes you to do a store/bank/market run and figure out if that silvers/click value is better or worse than the silvers/click average you make by digging. It's far worse for me (because I tend to spend a lot of clicks cashing in my listing dispro, kith, centro and hyperium on the market for 50% rather than selling them to the store), so I'm personally tossing everything that's not worth it's weight in silvers.
Sandy