use it on armor. just hit 34 and make beating the high level content that much easier for yourself. you'll get more and then you can ascend the gear you want and the weapons you want

stockpile until you know exactly what you want to wear and use

Legs For several reasons 1. Ascend an exotic helm, BOOM light 42 2. Buy PoE gauntlets from Variks BOOM light 42 3. Do ToO, buy chest piece from Brother Vance BOOM light 42 4. Use etheric light on a leg piece BOOM light 42 Aaaaaand youre level 34

Always armor first till 34. If you buy the gloves with your armor core (you should), that means you are likely using an exotic helm or chest. Personally, I would use your etheric light on boots first. The only way this backfires is if boots are the next weeks sales. (Which there is a strong chance of since they are considered the second lowest priority armor). If your gloves and boots are 42 light, then you can swap between wolf chest for blade dancer and symbiote for gun slinger. Lastly, if you have 3 pieces of 42 light armor, you can drop one if you like an exotic better. For instance if you followed my suggestion and ascended you boots, you don't have to use the gloves you bought to hit 33, any exotic will do, which lets you run don't touch me for blade dancer. Then, only you get your next etheric light, ascend a helm or chest, go back to PoE gloves, and you are 34.

You could actually reach 34 this week with that. Ascend a piece of legendary armor, ascend a piece of exotic armor; you're now 33. Do POE 32 then 34. You'll get an armor core from 32 which you'll be able to buy a max level armor piece from variks (I got some gloves, so I assume that's what you'd have available too. So don't ascend gloves beforehand). Then from 34 POE you'll get another etheric light to ascend your last legendary piece. Could try 35 after that.

Dismantle it

I would save it. What if you ascend legs and legs are what you earn next week. I would not ascend until you see what is being offered tuesday.