Starting fresh at new server, need help!

I'm a long time player since official League of Legends launch in 2010. Back then, I just moved to Japan and there was only one server, the North America server. Ping wasn't so bad (always hover between 100-150 tops), so it was THE server for me. I played on SR heavily until the release of Dominion, and switched to Dominion heavily until ARAM was around. Switched to ARAM exclusively ever since.

Now I just relocated back to SEA , and I would like to play again with friends on SR. But I have some serious issues :

1. Starting back fresh. I have almost everything unlocked at NA Server. I prefer to leave my NA account intact,(no transfer), and just focus on my favorite champs and roles.** So I need to plan my purchase order right, considering Im prirotizing some old cheap champs>Necessary runes>my fav champs**

2. Out of knowledge about current meta. Among my friend, I use my knowledge as a weightstone rather than my mechanics, and since Im really out of touch since S2/S3, I'm about as good as a dota player switching game.** I know we are in the preseason and everything is volatile, but a tl;dr shifts in favors would be nice to know.**

So I would like to have some input on :

1. Which champs do you see have high value of purchasing (either can fill some role with at least decent profficiency at it, or be good in said role without bottlenecking myself)

2. Which champion that I like that pertains to issue (1) :

If anything, I value CC>Durability>Damage. In short, I prefer champs that has good teamfight contributions, and heavy cc with a dash of support. When it comes to lane preference, Support>Jungle>Mid>ADC>Top

Champs that I like, according to Riot filter (not in order):

Mage :

Assassin

Fighter (my number 2 fav. Was my main/go-to champ back then. Had a few new friends when I played him) ( Really love his rework. Was considering as a new core champ if I ever play SR again) (only pheonix stance) (my awkward guilty pleasure champion. I hate his aesthetic and theme, but I acknowledge his power is often underrated by most) (one of the champion that my friend wants me to play when I jungle, in his prime)

Tank (By far my fav champ. I played her heavily on Dominion even. Leona is one thing I wouldnt put off. EVER) (Was my Dominion main post-rework. I read good things about her in SR until some recent nerfs) (probably my main in season one? was too long ago to remember)

Support ( I havent really played him so far, but his W eating ally is right up my alley)

ADC >

Special mention : . Because I like being an asshole to ruin another people's day.

Accoding to my close friend who sticked with me in all my LoL history, my top 5 champ(that I do good, even though I may not like playing them, or notice I good or confident at it) are Braum, Elise, Draven, Viktor, zyra(@support).

So there we have it. I would like to hear some inputs and advice regarding restarting the game again from zero on another server, especially in regards to spending my IP wisely. I don't see myself churning RP much other than exclusive skin. Thank you in advance!