I am new to PoE 2 and I have some build and general questions

Hello. I started playing PoE 2 a few weeks ago, and my buddy recommended I play spark sorceress. I became completely obsessed with the game. I tried to go into the whole experience blind without using build guides/wiki resources or anything like that. I recently gave up on that because there were certain aspects of the game I couldn't figure out, but there are some questions that I feel other online resources have been unable to answer.

1. Why does my loot filter highlight seemingly worthless white bases?

I understand the stellar amulets. I listed one for sale and someone whispered me and offered me 25 ex per amulet and explained the situation with chance orbs and astramentis. However my loot filter also highlight white-rarity heavy belts- and white rarity sapphire rings. Is there a market for these items, and if there is and I pick them up, will they be as easy to sell in bulk as stellar amulets?

2. Are any bosses in this game profitable?

When I first started playing I assumed that boss profitability would be proportional to difficulty. It turns out the community that plays this game is so good at it that boss difficulty is a non-factor, and people running bosses have a 100% completion rate generally and the resultant unique items are just priced mostly off of rarity. I really genuinely enjoy the boss fights in this game, and I was wondering if there is any boss in the game that is profitable over a large statistical average, or does the cost to access the bosses just make them a gamble?

3. Where can I find the equation that determines mana regeneration rate?

The in-game tooltip states "Every one intelligence grants +2 mana. Intelligence does not grant damage to Skills or any other benefits except where specifically stated." But when I increase my intelligence, and my maximum mana increases, my mana regeneration rate increases. I assume that means mana regeneration rate is partially determined by maximum mana, but I don't see that indicated in-game anywhere, and I'm curious if there are ways to scale mana regeneration rate aside from increasing maximum mana and getting mana regeneration rate on gear/passives.

4. Do better builds mean more profit?

I've pretty much running through the t15 maps I'm doing as fast as possible with very low interrupt time for casting spark. If I make my build better, is there a way I can make my maps more difficult and more profitable? I've heard of "juicing" maps, but I don't quite understand what that entails. Currently I use an orb of alchemy on all t15 maps I pick up, and then I use a vaal orb to see if I can turn some of them into t16 maps, and I delete the t14s. As I am pathing around the atlas, I head towards towers. I alternate between slotting a breach tablet and delirium tablet whenever I go to towers. After I finish a tower, I path towards the next tower while hitting all of the maps in-between that have breach and/or delirium. This occasionally results in incredibly difficult maps that are t16 and contain both a breach and a delirium mirror. Are there ways to make the maps even more difficult, provided my build can finish them?

5. Are there hosts you can pay to map with?

I absolutely love mapping. It is my favorite thing in this game. I have probably completed over 400 maps at this point. But sometimes I get tired of pathing around the atlas and taking maps out of the bank and just generally having to use my brain at all. Since there isn't some sort of "endless" or "horde" mode that I know of in this game, I was wondering if something akin to an "atlas host" existed. Someone who will pick the maps, choose where to slot them, deal with the tedium, and I can just go into map after map and kill stuff. I am completely aware that what I am essentially asking for is a friend, but I don't have any of those that play this game, so someone I could pay 1-2 ex per map to not have to think would be amazing.

6. General build help

I've attached my skill gems, my gear, and my passive tree. I was wondering if anyone more experienced than myself could point out possible obvious issues that I could fix. Also generally I am hesitant about spending my divine orbs since I don't really know what constitutes and upgrade and what doesn't unless it's a unique with better rolls. If anyone could tell me what the weakest pieces of gear on my character are, or what my next upgrades should be, I would appreciate it. current budget is 25div.

7. let me help you!

It would be selfish of me to come to you all in search of knowledge while offering nothing in return. If you want advice, I know nearly nothing, but I'll tell you anything I do know! If you need your 4th ascendency, I got you, hmu and we can do the carry later tonight. If you're interested in playing the build, I can tell you what iterations I went through while leveling and what felt best!

stats

yes I give ms paint lessons

gems

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tree 2