1. Do Unbreaking-enchanted electric tools' energy spending rate decrease?
Nope, electric discharging doesnt "damage" the Tool itself (you know, "discharging") and therefor the Unbreaking is useless.
2. Do a (Fire|Blast|Projectile) Protection-enchanted QuantumSuit Bodyarmor or a Feather Falling-enchanted QuantumSuit Boots have chance not to spend energy?
Enchants are not causing any Damage to the Armor when being used. The Protection Enchants work on the Armor (Feather falling is pointless unless you want to use discharged QBoots), but you will still loose the same amount of Energy. The Enchants even work on completly discharged Armor so they are quite useful.
3. Do Fortune-enchanted (electric) treetaps' Sticky Resin drop increase?
Fortune works only on Blockbreak and then only if the broken Block supports Fortune. The Treetap uses Rightclick to get the Resin out, so Fortune doesnt work. However, I didn't test using a Fortune III Axe on a Rubber Tree to get more Resin when chopping down the Logs.
4. Do Fortune-enchanted wrenches or lossless-mode-disabled electric wrenches' chance to break machines decrease?
Fortune doesn't work at all like that. And Wrenches are not really regular Tools, I doubt you can even enchant them. Same for the Treetaps.
5. Why nano sabers can't be enchanted with Sharpness, Knockback, etc?
You are not supposed to enchant Electric Tools at all (in newer Versions), and the Nano Saber is not a regular Sword so the Enchants are like for a normal Mining Tool.
6. Why chainsaws can't be enchanted with Sharpness, Smite, or Bane of Anthropods?
Cuz they are an Axe, NEXT.
7. Why mining lasers can't be enchanted with Power, Punch, or Flame?
Because it is not a Bow. And it wouldn't work anyways.
8. Do Thorn-enchanted NanoSuits or QuantumSuits' energy be consumed when Thorn is activated?
The whole Suit is getting consumed occassionally. I already lost some electric Armors due to that, when it was possible to enchant them through an exploit.