OK. So I've started to learn some advanced tactics from playing some games with more experienced folk and watching some replays. I figure I'll share some of what I've learned here and you folks can chime in with your own tips or tell me if perhaps I have the wrong ideas.
Game openers - apparently the higher level games can be a bit more heated first thing and this should impact the first skill you begin with. I was laned with jona (jax) as morgana. I always chose to get my AOE attack first because I rarely took a shot at a gank until level 2 (when I got my stun). This way, I'd just work the creeps over and help push the troops along. Well, apparently pushing the troops along early isn't the best idea. In fact, it seems that the ONLY time early that you should be even AAing the troops is for last hits. In the replays and live streams I've watched, that seems to be how most everyone plays. Jona also indicated that for morgana I should always take my stun first, followed by shield. If I had gone this route with him using jax, there are pretty good odds we'd have scored an almost immediate kill. So, I'll likely change my build up to go this way in the future. The way we were playing was that I'd go for a stun, jona would jump in and dmg the enemy up, and then I'd shield jona so he could push a little further. I'm not used to playing with jona and that cost us 2-3 kills/deaths, but it ended up being an easy win. Jona was good at barking out orders which was useful though.
Denying exp - in the scenario I described, it was jona and I vs 1 solo enemy up top. As we were pretty aggressively harassing him, that meant we could deny him exp and last hit gold by keeping him a certain distance from the creeps and then only last hitting ourselves. This really only would work if its 2v1 or 1v1 and you have a nice health adv over your enemy, but the goal is to keep the enemy far enough away from the creeps. You should NOT aa the enemy creeps so that the creep fights take place near you and not your enemy.
Another denying exp thing I learned was through a replay. It was a dr mundo vs chogath in the top lane. Mundo eventually wore down chogath and cho had to recall to base. Mundo rushes up to the tower with a creep wave and gets the tower down to maybe 10% hp. But then he retreats with the tower still alive. He did this so that his creep wave would get destroyed by the tower (while his creeps also did dmg to the tower). If he had continued killing the tower himself, the enemy chogath, which would have been back 10-15 seconds later, would have gotten the exp from that creep wave (eg the wave that would still be alive if mundo killed the tower off. So, using this method, he got the tower down to about 2% hp, an entire creep wave died off which kept chogath from getting additional xp/gold. And with the tower so low, it wasn't going to take a super long time to kill off that tower. Anyway, I think it was a pretty solid tactic as chogath lost xp by being forced to base, then lost more due to keeping the tower alive.
Anyone else have any useful tips or suggestions?