I really like the fact that we are getting closer to implementing this idea. Because I was curious, I ran the numbers for a single skill potion at level 250. I came up with CF=50, RF=11.25, LF=1.25 & EF=.15. Obviously rounding will change those to whole numbers. If the conversion idea for changing CF to RF or others is implemented, then even a level 10 player could make a level 250 potion by converting enough common items into common fragments and upgrading the CF to RF, LF or even EF if needed. I don't see a level 10 or even 100 player doing that very often as the ease of getting level 175 buffs covers most of the needs of low level players. And the gold cost was only 45,000. I ignored the time factor as it was a non-factor for me - plan ahead!
Where I do see this happening, is for players to make their custom potions in order to hunt titans or SEs that they might not be able to hunt otherwise.
If players concentrate on single skill potions, they will be able to make a whole bevy of potions from the - currently - worthless drops of a single hunt for their next hunt. I would anticipate making my desired next hunt potions and using the left-over fragments, making potions for my guild mates to benefit their efforts.
Doginal just beat me to the idea of single skill potions!
I think the skills should be restricted to skills that don't already have potions that can be made. ie, avoid AL, AM, BER, etc. I would love to get my hands on a AM250 for every hunt but is it fair to the people that go to the trouble/expense of making them to give everyone a cheap alternative?