Thanks for this! You make two interesting point worth some more discussion.
1) I can't believe I never considered this Fast Drug strategy, so I reread some rules to see why. I think the answer is that in older Traveller this strategy is more expensive than you say. Up to MegaT, Fast costs Cr200 and the antidote Cr900. In the MgT CSC I have (which may not be the most current), Fast is also listed as Cr200 with no antidote listed. I think the high price of the antidote gives away the intent of the rules, which is: "no, you can't cut the pills into 8ths, if you want to use Fast for less than 60 days, you need to cancel it with antidote." Of course, It's Your Game (TM) as always.
Continuing, the cost of shipboard life support used to be Cr2000/100 per 2 weeks per person/low berth. In MgT it is now Cr1000/100 per month, so quite a bit lower. But in either case, a person on Fast is using 1/60th normal life support. So conservatively, could we not set up racked bunks in a stateroom and hold 30 passengers on IV drips for a week? I'm thinking about this from a story perspective: sure, the players might ask to use Fast this way, but I'm thinking about them encountering such a ship, likely operating illegally, for the purpose of refugee transport, mass improvised migration, and other unsavory purposes (perhaps not to every table's liking, of course). So I'm glad you pointed this out, including the low-rent "timer" strategy of trying to live through the ages!
2) The cost of living comment seemed odd to me. I use the MegaT rule of Cr250 x Soc per month for all upkeep, noting that this does not apply while in space, and that once Soc > 9, expenditures would probably be higher (at least for NPCs). So I checked my copy of MgT, and the upkeep chart is pretty close to this! Cr1500/month at Soc 7, accelerating at Soc 10, and not applying aboard ship. Finally, I looked up real World GDP per capita at PPP (which by definition is a good approximation for per capita income), and in 2019 that figure was USD $18400 = $1533/month. So it all kind of holds together, surprisingly so. What do you think would be more reasonable pricing? There's clearly no right answer here as it's all fiction and one could go full cinematic and ignore all economics, but I'm interested in different solutions.
One comment on costs and TL: I use older rules for exchange rates that set up a system where Credits have different values per TL, and for a given TL the costs of that TL's goods are same across all TLs. In other words, TL 15 Cr buying TL 15 goods have the same purchasing power as TL 8 Cr buying TL 8 goods, and so travellers carrying TL 15 Credits (the base assumption in my setting) have some additional purchasing power on lower TL worlds. This takes some judgement, but it basically means that you can use the same equipment list regardless of TL, and at a given TL all goods that TL or lower are available for the listed price. Lower TL goods on higher TL worlds are often lower, but not always. For example, a long compound bow is TL 2 and Cr125 on my lists. I just did a quick price check and a modern compound bow is USD $250-350, so Cr125 is a steal! More importantly, the point is that the cost of a good like a bow that changes marginally across TLs remains relatvely constant (i.e. implicit inflation). This all works for me, but there could be other approaches.
