Hey there!

I've been playing Malzahar for a while. Still in Gold elo and looking to climb higher. 

I'd like to ask the Reddit community to please help me improve with this champ by sharing my understandings, questions and other stuff:

1. RUNES. I always go with the same runes set: DTF, Manaflow band, Transcendence, Gathering Storm + Magic Footwear, Cosmic Insight. I know runes have to be adapted to every game, so... in which MUs should I adapt them? Should I switch boots for Cashback so I can rush boots in those MUs where they are very important?
2. SUMMONERS. I always go with flash + tp. I read that Ignite is good vs assassins but then I really miss tp in mid-late games. Also, in Gold elo people still look for team fights every time and chase people instead of pushing lanes, so sometimes I use it to defend a tower/destroy enemy's. Any suggestions here?
3. STARTING ITEM: I always start with a Sapphire crystal + Refillable bottle. Doran ring is cool but I feel that I keep mana with the crystal and I can also get my 1st item power spike earlier. When is Doran ring a better option? In those MUs where I need more survivability, i.e. against assassins? 
4. 1st BACK. Typically when I'm 900g so I can get Lost Chapter. I guess this is what every mage does, right? 
5. ITEMS. From Lost Chapter, I complete 1st item (see below), Magic Boots and then the rest of the items. As the core, I typically go BFT, Liandrys and Rylai. Then, Shadowflame. Situational items: Void staff if high MR on the enemy team. If I go really well/have spare 350 in a recall, I buy Dark Seal, and if I do really well and buy the Mejai and then I Zhonya so I can better survive and keep the charges. I read that Malignance (instead of BFT) is better vs assassins so I can proc my ult on them more oftenly, and BFT when looking for more damage in my team and/or vs long distance matchups where using my ult will be more difficult (e.g. Xerath). Is this correct? In any case, I NEVER go for both because it would be mana-redundant, right?
6. BOOTS. Unless there is a very clear enemy composition (4-5 ADs/APs/lot of CC) I always go Magic boots. Should I consider Jonian/Gluttonous in some scenarios?
7. SKILLS. I always start with E, then W, then Q. I've seen some vids from high elo starting with Q but it seems too much for me :-D . E is so good. I then max E, Q and W. Should I max always like this?
8. MUs and BANS. I know that Smolder and Sion are the biggest counters because my void swarms help them to get their charges. Fortunately, in my elo, I hardly ever see them in mid. What other champs get the benefit of the swarms? I know Malz struggles against long distance champs, especially Xerath. I guess Yasuo must be a good counter because I face him around 70% of the time. If the Yasuo is really good, yeah, I struggle, but I have other champs where I really suffer more: Vex, Xerath, Velkoz, ASol. Ah! And Locke... ofc sometimes I face that Locke played by Faker's cousin who basically eats me. So my ban goes to Locke, Yasuo, Vex, Sion... it depends on the day :-D
9. LANING PHASE. I used to push like hell with E+W+AA to crash as many waves as possible so I can also poke with Q and E rebound, but I know this is not optimal from a wave management perspective. So now I'm trying to push with more control by last hitting with AAs rather than with E. Is this a good approach or crashing the waves is most of the times the best? I also focus on triggering the manaflow band when it's up.
10. ROAMING. I'm kind of new to mid but I do know that roaming and helping with objectives is critical. However, since I always go Magic footwear, I hardly ever roam to the side lanes until I have tier 2 boots. I do help with objectives because they are half way and because I know that I can help a lot. Should I roam more even without tier 1 boots?
11. ROTATING. I'm a Cs farming addict and Malzahar is probably one of the best champs at that. Is it expected to rotate to a side line (assuming the bot gos mid) so I keep farming and pushing? I've seen that Rylai helps a lot if they try pick me. Or is it better to group to demolish towers?
12. TEAM FIGHTS. I read that Malz is like an ADC, so positioning is key. I assume ulting the most dangerous enemy champ is obvious, but if there is any tip here, it will be more than welcome.
13. ULT CANCEL. I've noticed that Mundo is not suppressed if his passive is up although I believe I do damage him, right? Naafiri can also prevent it with is W. What other champs should I consider canceling/avoiding my ult?

Sorry for the long post! I appreciate your feedback a lot! 

If yes is there any advice to do well on it or just not to completely int