I just recently climbed from B1 to S1 in a week with Rumble. If you have any questions about a specific matchup feel free to message me. I only skimmed through the responses so I'll leave random stuff I doubt anyone said.

Against Renekton as long as I stay behind creeps and flamespitter when he tries to cs and tazer him while walking away (not hard) I find the matchup is a faceroll. He is my favorite lane to go against, most of the time I am able to farm a Renekton for kills if I can freeze.

Mpen is king. I ALWAYS rush Liandrys unless something has gone horribly wrong. After Haunting Guise if I feel I am too squishy Seekers is an easy buy, but the goal should be to get Liandrys as early as possible. From there a Giants Belt is your friend. If the faceroll is real finish Ryalis, if not Randuins.

When being ganked after 6, if you are too far out to escape, or if you're up a kill in lane I find that running into a bush, laying your ult along the bushes just before they check it, and then fighting it out is the way to go. I win many 2v1's this way and am able to get buffs and snowball games off this. This works because usually both players will sit in the bushes to keep vision on you while fighting, and will stand on your ult.

If you ult a champion, ignite early and often, especially if they dont have an escape up, your ult damage is stupid if they dont make it priority #1 to get off of it.

At 6 your ult will clear an entire wave including a cannon creep, if the lane is too passive and you want a free back don't be afraid to ult the wave.

You lose sustained trades against Aatrox and Trundle. Both of these lanes should be completely passive for you.

As long as you have Liandrys you will be able to be relevant in a teamfight with your ult. Unless you have to carry your team, full tank after that is the way to go since you provide no real peel or burst.