Is Biochem gains minimal?
Yes. It used to be, that some serious guilds would even require every raider to have biochem.
By now, the difference between Biochem and not Biochem is not so powerful.
So, I will be the naysayer. No, I don't think Biochem is overwhelmingly required. I used to have Biochem on 70% of my characters - i use percentages because I don't know how many characters I actually have across all the different servers in the galaxy =) But, suffice it to say, I have at least 30, though only 5 are max level.
I say used to, because, Biochem has been nerfed over time, and just isn't that great anymore.
The 15% health on use (health) medpac was huge! But, once that got nerfed, the difference between biochem and the rest was pretty much blurred.
Sure, perhaps you "save" a little money, on the reusable medpacs. Say, for example, the health one that can heal up to 6800.
But, the craftable - non-reusable one is "better" because it also includes a small 1500 or so, additional heal over time. I say "better" because really it's not that big of a deal =) (and honestly, I probably would be more satisfied with the reusable one). =) But, technically, the one available to everyone is better than the biochem specific health medpac. Also, they are BOTH only usesable once per fight - so there is no advantage to a biochemer.
There is also craftable stims that persist through death, for 90 minutes(?, 2 hours?). Those are every bit as good as the reusable ones for biochem - so yeah, never having to make any is better than actually having to make some, but there is no major cost if you only need to pop one every few hours.
The adrenal is ok, and can be popped, but when you look at what you gain - the benefit is usually 2-4% for 15 seconds. I don't know necessary that it will make a difference. On my biochem toon, I still use it. But, it's mostly a placebo effect =)
Maybe a month or so ago, I dropped Biochem on most of my highly active characters, because as long as I have one biochem character, I can make all I need for the rest of them. And, let's be honest, the mats are REAL easy to get, and you can just send out your companions all the time, and always have enough for everyone.
The best argument in favor would look like this:
1. you run ops - and need (should) to have max adrenals, stims, medpacs on hand, at all times.
2. you have no other character with biochem, that you play regularly.
3. your guild does not provide them to you.
4. you don't hardly play at all outside of ops.
5. and don't have 25 million credits in your account - to buy them from the Galactic Network.
6. you don't have a mate to craft them for you.
Then, perhaps it's worth it to level biochem to 450.
All that said, I can't really make an argument that anything else is terribly more useful if you do Ops - as a main focus.