I'm going to be nice. I'm going to rewrite your paragraph with a bit more of a humble tone.
"Hello everyone! I'm ExNaTions. I'd be really interested in joining up on a ranked 5v5 team, or possibly even starting a new one. I'm primarily a mid player with a 12-3 record with Viktor, and a 1100-1200 rating. I have some past expierence with playing on ranked teams that unfortunately broke up due to some inactivity from our members. I'd be more than happy to play with a few games with a team to see how I fit it and if I mesh well with everyone. I really enjoyed my past ranked teams, and I hope the same could happen with all of you! Leave your name if you want me to add you, or feel free to add me and shoot me a message at my IGN: ExNaTions. Look forward to talking with you all!"
Also, if you do indeed start one up, I'd be down. Don't play much ranked, (Ragers put me off of it personally), but I'd be willing to start up on a team. I mostly play bot lane, though mostly AD carry.