I am not a big fan, but whaddayagonnado? To save grief, and realistically it does not make all that much difference, this is what I do:
Now mind you I have craftsmen who can make any weapon/item with the correct materials. My strategy is to equip crafted 2As when I hit the level for use.
Level 45: Get and equip your Newbie Items. Start collecting level 51-52 LIs for later.
Level 51: Slot your 51s (and when you can...52s) to fill up your available LI slots. Keep using newbie items until they are max. You probably won't hit max on both.
Level 53: You can now use the bartered LIs. You should now have a system of grinding relics in mind. These levels (53-59) are easy to obtain so get to grindin'!
~Level 57, you might want to find 57 items with decent legacies and replace your newbie items. I would not slot any relics above tier 4 yet. If you are lucky to find a 2A for your level , equip it. I would replace the beginners with a 2A if I came across one earlier.
Level 60: Obtain and equip level 60 2As. Dump your lot and merge relics to get a set. Tier 6 relics are probably ok, and you wont lose sleep by destroying them at level 65. Look into crafted relics too.
Level 65: De-con your 60s, rinse repeat for level 65.
~level 70 Now about here you have to decide if you need a boost or not. Really depends. If you have good legacies or a 1A level 65, I would keep it until 75. I think I may have changed out 1 item on one character here.
Level 75: Dump your lot again and re-ante for crafted level 75 2A. You also have to get a bridle if you don't have one. I never put much effort into bridles, but you should have one. I just use the level 4-relics-->brindle relic ones.
I use my 75s right up until 85.
Level 85: You know the drill. There is also a 2A Bridle reward from a quest arc (epic?)
At 85, I level all my fodder items to 60. I do not level any bridles.