Touch Trigger is very very poorly described and there's a lot of reasons why putting a preparation into a bottle or bag wouldn't work if you go by how a touch spell works... Also I swear I recall hearing that liquid mediums aren't applicable for preparations but it doesn't say so in the book. But, the reasoning is, a preparation is a magical thing that has an effective range of touch. Touch spells and any powers that have a range of touch (and any "touch attacks" like shock gloves, but that's different) do not need to physically touch a person's skin-- If they did, they'd be nearly useless in combat. Instead, it's about auras intersecting. Logically a touch trigger prep would be the same, meaning that simply a bag or bottle wouldn't be enough to stop someone from activating it when they held it. It's about internal consistency.
An alchemy focus is only available at F4 during creation unless you take Restricted Gear to get an F8 focus. But the extra dice doesn't matter-- Look at my post; the dice pool of the user doesn't make a difference. If you have 30 dice at Alchemy and make a F6 Prep, it will most likely be Potency 4 (due to limits and the prep rolling 6 dice) and at most 6 and roll 10 to 12 dice when activated-- Not better than a sorcerer. If you increase it to say, F8 preparations, you begin to start really getting hurt by drain and will likely go into a run with only four or five preparations (unless you don't mind starting with half your Stun track full). Also, as the Force increases, the prep rolls more dice to "resist" and thus less of your net hits count... So on and so forth. You can literally have an infinite dice pool for Alchemy but unless you're burning Edge every roll, it doesn't matter because the limits and opposing rolls are what hurt.
Also, yes, you can quicken spells on your allies. You can quicken literally any spell with a duration of Sustained. You can buff all your allies, you can have some pet hellhounds that are buffed out the ass... You can easily quicken a lot of spells considering there's no limit and it can cost you only 1 Karma per spell.
If you really really try you can find some use of some alchemy, but it's not worth the investment when spells and sorcery is so much better. Having to buy the skill is one thing, but then you need to buy a focus for it to be even almost not terrible along with buying and learning spells as preparations. It's not like someone spending 12 Karma on Pistols 3 and picking a gun off a dead ganger.