Highers make decent enough anything. Iirc, their primary racial scales with willpower, which makes them a pretty solid match with temporal wardens (whose primary stats are will/mag, followed by str or dex (or both) depending on what they're leaning toward). Less so with shadowblades, but SBs will want to build a little willpower to open up some of their more expensive sustains so it's not a total loss. The extended max visual range dovetails nicely with an infravision spec'd SB.
SBs get speed primarily from essence of speed (temporal tree) and momentum, but both are pretty late game due to how expensive they are. Maybe blinding speed and some conditional stuff (Shalore racial, fire harmony). Before that, they're primarily burst melee guys (flurry/sweep with the added darkness damage) with high mobility (controlled phase door), so it's nothing really fancy. Remember the second tier talent in the tree that has willful combat is an instant, so it doesn't take time to use. SBs can also invest in the phantasm tree if they're fully plucky; there's some nice stuff in there.
Alchemist damage output comes naturally; max the bomb tree except shockwave (which is mostly junk), and then invest in two infusion talents (I tend toward fire and acid; most tend to take fire and one of the debuff-able infusions. Fire hits a bit harder, but the crowd control can be useful). Generally you'll want to use the highest tier gem you can get access to, as bomb damage scales with gem tier. Other than that, you just get channel staff to at least 3/5 (initially; you'll max it eventually) and max out staff mastery. Get a nice staff and channel will pretty easily be chunking off 1-200 HP per turn at range by the time you're twenty-ish. You can invest in the heat tree, but it will never do more damage than your bombs can; it's more for supplement while the bombs are cooling down than an actual primary damage source, though there's some utility, too.
Golem durability and damage comes from the first two talents in the basic golemancy tree, the gem and runic golem talents, and supercharge golem. The first two are no-brainers, simple passive boosts. Gem golem allows you to change the golem's base damage type (so a golem with an amethyst in its eye will do arcane instead of physical when it beats on something, ferex.) as well as adjust the golem slightly as needed to lean toward damage (+% alldam or stats) or durability (+% resall), usually you'll gem the golem toward resistance to stack with the golem resilience talent. You'll also want to stick an appropriate gem in the golem's armor with imbue.
Runic massively increases the golem's regen (boosting it further with a verdant/eyal heavy or massive armor is possible! Chainmail of bloodletting is also pretty good.) and allows you to stick extra offensive runes on the golem (I lean toward the fire and lightning one's, but acid wave can be good, too. Don't use frost spear. Rune of the rift is a possibility on a magic-leaning golem, but requires willpower to land easily, so is sub-par.) for extra damage. Know that the golem starts with three inscription slots, same as the player, so 5/5 runic golem actually gives the golem six, total. Get two shield runes (and possibly the rune of absorption or whatev', if you happen upon the troll hedge wizard) and then load up on damage runes.
Supercharge gives the golem massive healing as well as insta-resurrects the golem if it's dead (unlike refit, which takes many turns) -- you can use it two ways, mostly; preemptively at the start of a fight to lengthen the golem's up time, or save it to resurrect the golem after it drops. Sometimes if you do the former, the talent will have came off cool down before the golem pops, letting you very much massively extend the golem's presence in a fight.
Freeze is an excellent single-target debuff and alright damage. Most archmagi stick at least one point into it, more id they've got the points to spare. Stone wall is pretty useful, but somewhat situationally so, and you can get it on a hat. YMMV, I've personally never really used it much.
The +% damage on staves effect everything. Bomb damage, heat tree, channel staff, smacking things in the head, whatever. Doesn't boost the golem (though it does boost the damage on summoner summons! Iirc, anyway.), but that's about it. Vilestaves are excellent on an acid/fire alchemist, especially if it's a greater prefix ego.
Questions are fine, heh. There's also the t4 forums and the in-game chat, if you want second opinions or on the fly advice or answers.