I've been an herbalist on every character I've played. The benefits out way any 'grind' (and that grind has gotten significantly faster for herbalism with recent changes).
Some points:
-- I dislike the idea that all potions will have higher caster levels. Part of potions downside IS the lower caster level, meaning they are more easily dispelled, as well as lower duration then bringing a caster. It would be interesting to possibly make some ingredient you can add to potions to boost their caster level, but I think the generic level is quite sufficient, and does not need boosting. I think id' be cool to add more recipes to some of the more moderate potions to extend duration though (Think something like adding a 'greater strength herb' to the standard honey-lily strength combo, to provide a level 10 bulls, rather then the level 3. Make more unique combos for interesting effects, to give the stronger herbs a use besides hording for Greater Stat Potions. I think that could be a cool addition, give herbalists more play in the potions and recipies, and could make some uses for some of the more worthless herbs available.
-- The DC formula is well balanced. All recipes but 3 follow it (not sure why these ones don't??), and there is a plethora of recipes in all ranges to utilize. The 'jumps' from 22 to 32 to 42 to 52 aren't enormous, you get yourself proficient with the 22s, then have a 15+ on succeeding the first attempts of the 32's, etc. There are also potions of 24, 28 between the first tear, dc 40 for mid jump, and 43, 49 for the pre 52 jump. Don't really see any issue with the gaps, all in all. I've done herbalism on every character I play, and recently have trained quite a few herbalists in character with our organization. Certainly easy to make these jumps, Especially if you get muses involved.
-- I see complaints about heal potions, they've been in game long enough to be stockpiled heavily. If they are an issue with PvP, removing access to them will compound the issue with legacy gear in general... its about who still has stuff left over and willing to pass it on or keep it in game. PvP is always about consumables when between two equal combatants, who'se more prepared, don't like it, prepare more. This doesn't just go with herbalism, but any kind of grinding for consumables. Removing them won't balance any sort of playing field. Just limit the access to those that already have them. I'm against removing them, completely. Find other suggestions if they are a problem, or brew your own and even the PvP encounter.