http://www.sc2replayed.com/replay-videos/16978
Feedback please?

Anything I could have done better etc?
Right, I'll try to keep this one reasonably short and concise.
Build Order
So you're opting for a gas pool opening, leading to a very secure natural expansion. Not only a common opening, but a very strong one as well. However, your execution could be a lot better.
We start with a gas on 14. The timing of this is very particular, in that we can also start a spawning pool on our next 14 supply point. If I put my drones on gas immediately when the extractor finishes, I should have 100 gas for speed and 250 minerals for ling speed and a queen right when the pool finishes. It's a very sweet timing.
If i'm constantly building drones, I should then be able to afford my hatchery around 21 supply. Yours was around 18 supply, which is more common for a 15 pool straight into hatchery opening. This demonstrates a significant number of 'bumps' in your initial build order. After that, you seemed to have a decent idea of where you were going, but your lair and subsequent spire -> muta tech could have been way earlier.
Units vs Drones
Yes, by all means have units on the map. As you climb the ladder you're going to start getting drops from terrans cropping up all over the map, and you'll need units to react to large attacks. However, what this game should have taught you is that attacking a well turtled terran with tanks on the high ground and bunkers with almost pure lings is a waste.
Furthermore, the cost of that initial attack wasnt just the lings that died, but also the opportunity cost of building drones, which is extremely significant, especially going into the midgame when you want to be expanding your economy quickly. Because you made so many zerglings, you struggled to saturate your main and natural for a long time, and only once your third was up did you have any real saturation going.
So here's my suggestion. Have some zerglings on the map. Do increase the number of units you have out over the course of the game. Start with 4-6. Keep at least 2 lings near your opponent's base to scout for attacks and look for unit composition. The rest of your zerglings can be scouting around the map alongside overlords to check for hidden expansions/drops. This means if they decide to move out, you have the time between them leaving their base and reaching yours (a fairly long time in general, especially on larger maps) to suppliment with more units, morph banelings etc. In general only morph banelings when you know you'll need them. Otherwise the gas will almost always be more useful somewhere else at the time.
Applying these thought processes your games will give you more drones, faster tech, and (perhaps counterintuitively)
more units over time.
Final thought: Interesting hotkey setup. I'll have to try that one. I've just been using a hotkey for queens and a hotkey for hatcheries.
Success! A short strategy post
EDIT: In general be careful about attacking players in their natural unless you know you'll do damage. It'll be the point at which they're generally best defended. It's ok to sit back and stop them from taking expansions while you prepare your ultimate deatharmy of doom and destruction.
Oh and more upgrades!!!!!