[Actuarian]

There really isn't one good strategy for construction. Just like everything else is in dom3, you can't consider it in a vacuum. It's a piece of a bigger puzzle.

On a strategic level, you can coordinate construction with your beginning scales. For example you can offset choosing drain 2 by building research boosters. This miniminizes the percentage impact of the drain, since reserch items aren't subject to any research drain effects. Also, since drain doesn't change the number of gems needed for construction, construction is somewhat more attractive relative to spell casting when you choose drain. A good beginning strategy could be to choose a drain scale with growth and productivity to increase (resources and income, focus on troops and items and not put as much emphasis on magic (except focus on construction research). You could then go for a bless strategy and choose a dormant pretender with a one or two high paths to help bless effects in combat, like water, fire, earth, nature and/or blood.
On a more tactical level, you can build items based on troops in an army. For example, if you have an army of poison immune troops, make a poison immunity items for your commanders as needed, then cast poison cloud (several types of troops also naturally create a poison cloud).

Other of my early favorites are regeneration items for commanders with decent hit points, magic path boosting items, reinvigoration items and decent light armor for spell casters.

For commanders who you have just sitting a the back of a battle, make them a bow, an item that casts spells, an item that improves morale, or an item that creates fear.

Finally, some items are particularly good against certain troops. For example, if you are fighting a bunch of undeads armies, equip your non-spell casting commanders with items that cast anti-undead spells, like the herald lance.

Finally, for tactical item use to be successful, you need enough labs so its not a herculean task to change items.

A personal favorite of mine for a holistic construction strategy is to choose Pangaea with drain 2, luck 3, turmoil 3 and productivity 2 (for extra resources). Choose an imprisoned pretender with high earth and nature for reinvigoration and regeneration. Create an army of blessed centaurs and put them with you prophet and you have a formidable army (berserk, reinvigoration and regeneration). Buy Pans and they will generate hordes of maenads. Buy centaur archers and other longbowmen when possible. Construct sacks of wine and cauldrons of broth and summer swords to supply your berserking hordes. Construct Ivy crowns and generate armies of vine ogres. Construct fear generating items to send with your armies. Build a cheap temple in every province to spread dominion to enemy controlled provinces. This combination will make you rout enemy troops almost every time, even when you are numerically overwhelmed at the beginning of a battle. Make research boosting items as soon as you have the right paths and gems. Build path boosting items as needed, especially thistle staff.