My opinion about this:
Why would we (players) want a smaller premium time?
In my very own opinion, it's somehow useless. It could only help our "fat farmers", with tons of accounts, to enjoy periods like events or boosts, or for example, to make a new quest and profit with it with a forgotten character/account.
For new players (ip based ofc), the lvl 50 premium ticket can help a lot the guy, that can, for example, get lvl 80 in one day (trust me, it is possible and rather easy) and make quests to be able to afford a full vip buying it in the market. This, together with a daily login reward of "testing vip days", will finish the deal. This could also be applied for retired guys coming back to play.
So most likely, this feature would help the "old players".
Actual situation of the diamonds in the server:
Diamonds are having their price increased due new uses for it, other than vip. Mega-stone unlinker, tm tasks resets, charms unlockers, etc. With those new features prolly increased donations, which is a positive impact to the server (not platinum/diamond, but the host itself). Small transactions of diamond, for example, ability resets, rocket balls, people most likely buy them in game instead donating for it.
Oh yeah, but to buy them in-game someone donated.
Sure, but no one will donate ONLY for this reason, Im pretty sure. So this new feature of smaller vips could increase the diamonds price in the market (since you are giving another use for it), but could not make much difference into donations (which is -or should be- the main target for staff, to keep servers running in the first place).
Also, for a game, its better if a player commit himself to play for a longer time, that's why most of the games that offer this "exclusive access", make promotions according to the "vip" you are buying, the more you buy, cheaper it becomes. This proposal goes exactly the other way around.
So, in my pov, this addition to the game would help only (or at least most) those guys that already have lost of cash (and accounts) from farming, with no actual benefit for regular players (in fact, if the price of the diamonds increase due this new extra use, would damage even more those kind of players).