1) giving a patrol or attackmove order can't be really called micro, but it makes a difference which order you choose
if you just want to move your airunits somewhere, better don't use the attackmove but a normal moveorder, your ints will fly far away from the route when they see a single scout in distance.
give ints an attackmove, when you're close a horde of enemy fighters, this way they'll attack them right away unlike with a patrol order, because they'd fly to the first point of the patrol route, and then start attacking. when just covering an aera with your airforce, feel free to use the patrol order.
"micro" is, when you directly keep control over your ints and use them as efficient as possible. for example, you see the enemy flying alot ints somewhere, try to sneak behind them and stay in shooting range all the time, you will decimate his airforce without beeing hit yourself.
air micro is very common with asfs (t3 air superiority fighters), but not bad with ints and already very useful with swiftwinds (aeon t2 fighters)
now, to some land units:
moving some units with the attack order is very useful, if they got long range (short range has to come close, and it will be a normal fight anyway... but they get stuck in each other making a lump of units which is very vulnerable to arty)
example units, where this is very useful (if you want to move them, but they're fragile and you can't always watch them)
aurora (aeon t1 tank)
mongoose and hoplite (uef and cybran t2 bot)
also you can do this with engineers (alt + rightclick for a attackmove), they will reclaim everything on their way and also a bit distanced from it. after they finished the task, they're idle again, means they're not useless patroling around
2)unit combinations? depends which faction you play, and if you want land/air/naval combinations. also tech matters, i just tell usual t1 combinations here
land:
uef: one scout, 4 tanks, 2 arty
cybran: one scout, 5 manti, 1 arty (sometimes an arty more, they're better since the last patch)
aeon: one scout, 5 tanks, 1 arty (sometimes no arty at all, depends if you need them for taking out point defenses)
sera: one scout, 3 tanks, 3 arty
usually, speaking of about 7 units, you often don't need anti air, as your own airforce (ints) should be able to protect them
air:
very usual to have one bomber per 5 ints, until t2 air is around (then often less bombers, even if you don't have t2 air yourself)
don't forget to build one air scout per 5~10 ints, and do exactly what its name suggests, to know what the enemy is trying to do
to keep air supremacy when you're t2 air, build another air fac and assist it with engys, and spam just alot ints.
gunships or torpedo bombers won't help you in airfights, and f/bs just barely (not as good as ints, for their costs)
naval:
well, this is a bit trickier, it very much depends what the enemy is doing here, and on the size of the map
if he doesn't have naval himself, build few subs and alot frigates. frigates are kinda cheap for their hp, also they got radar, sonar, aa (not for aeon), and a good range for their weapon
they're perfectly suited against hover units, that makes them very useful if you don't have hover units yourself but they pose a threat to you... but they're absolutely useless against subs
this means, try to win navy with subs, and build frigates only if you're not losing, at least on the t1 stage
in the t2 stage, it's completely different, because destroyers got very strong torpedos and good torpedo defense, they make t1 subs almost useless. but you can beat destroyers with a nice amout of frigates.
this in mind, you will have to spam own destroyers, lots of frigates, and cruiser only when you're about to win navy or need protection against air
uef got shieldboats, you will want to have at least one after building 2 destroyers, and cover your navy force with it. also they have torpedo boats, very very strong against subs, but in return their destroyer's torpedos are weak. this means, if the enemy goes for subs, build some of these. (you can find out by scouting
)
cybran has a stealth boat, it provides a stealth field, you will want to have one after 2 destroyers/cruisers, as cybran has long range t2 navy, and this boat helps them to be unseen while shooting down the enemy from far away
3)assisting a t1 land factory is almost useless, because the unit takes some time to roll out of the fac, while this you waste alot buildpower. just build more facs, and spam unit with them aswell.
it's only useful, if you're not able to build more facs, or in an early stage when you don't have the mass for a new factory but need more engies fast.
assisting navy and air t1 facs is ways better, because air will instantly fly out of the fac (you won't waste buildpower), and the engys don't take as much place as a whole navy factory, also you waste less buildpower because navy units have a long buildtime, the unit won't be done each 10 seconds
assisting t2 or t3 factories is a MUST.
(also for land)
this is ways cheaper than upgrading another factory, also the units are better than t1 units when comparing hp/damage/range per mass. it's usual to assist a t2 factory sometimes with 30 or more engys, to get more t2 units on the field.