Perhaps trying to be a friend to the viewers and uploading every week, or in some sort of consistent pace. I tried this and it boosted my subs but I haven't uploaded in weeks so my subs aren't going up very fast...
This, more than anything else, is what I believe has helped my channel grow so rapidly. I try to upload at least one video a day Mon-Fri, and one more on weekends. I then take a good hour a day minimum(every day, and if I can at least checking my comments 3 times a day) replying to comments, interacting on various forums I cross-post at(some places are nice communities when they realise you're not just there to promote videos) and abuse people on Twitter/Facebook. People are way more willing to help you with a share if they're your friend. If nobody comments, give them a reason to! The one video of mine which generated the most comments was when I discovered trains exist in a game by literally driving into the side of one... One other thing I've tried in the same game is to buy a truck in it, and ask for suggestions for naming it. Minecraft, ask for suggestions for pranks on fellow server users. F1, ask people to tell you you're great even though you know you're s***e. And jump on that comment as soon as they make it, and they'll come back and make more. Seeing comments gets more comments made.
I clicked on your channel link, and the very first thing I've noticed? One Channel layout, but no trailer. This needs sorting - don't make excuses, do it. Just a 30 second short will do, and you can find good threads right here on YTT explaining what should go into one.
Other feedback, you seem to pause a little too much, something a lot of people are guilty of - and it's not a normal pausing for thought, it's a full on stop. Try and reduce that. You're actually quite funny but the flow is non-existent. You have a lot of games, which seem quite obscure and there's also many of them. I see WoW and Rage as recognisable titles, and the only one that could be turned into a regular series is WoW - another regular series would allow you to build up a fanbase of people that would subscribe and keep coming back. It would also be interesting to know how specifically you're promoting your WoW videos, as you should be a lot higher if you post them in the right places.
Not got the money to buy a new game? Look through your back catalogue, I'll bet you've got SOMETHING there.
A big point here, your audio. I don't know how you do your recording, but it sounds like the mic is really close to your mouth ruining the quality of anything being picked up, and as a result the voice levels spike all over the place. My recommendation here is one I tried myself when I found my voice was coming over too quietly; I record the audio separately. Move the mic away from your mouth a good inch or three, and turn the levels down to about 80%. I find it's a lot better to then record your voice through Audacity, you'll need to find a method of syncing your audio up(I move the mouse over various objects on the screen and read them out so the two audio tracks match up, and edit that part out) but the quality will improve a lot. Better to make a quiet track louder during editing than try and turn down a loud one, you'll still get the spikes if you're eating the microphone. You can also balance Skype calls and game sounds a lot better just from recording your voice separately.
If you're already doing this then you need to invest in a better mic, I use the one attached to the Microsoft LiveChat LX-3000 and it works a treat(but I myself would like to upgrade further in the future).
Final point: got any RL friends? Ask them to review your stuff - and this is the fun part - and then to give you feedback in a b******t free manner. My network of friends is quite quick to tell me where I can improve, and if you don't have this in place then you need it. You need to work on your foundations before you can build the skyscraper, so to speak.
On a completely semi-related note, you say your slow internet holds you back with collabs? In what sense - I'm going to take a guess at physically playing games with people, as opposed to the upload speed? In which case maybe have a word with your ISP to see if you're due a free upgrade; I'm with Virgin and they periodically upgrade our download speed for free and it's now so fast that I've had to ask them to trade some down speed for up, it's that non-noticeable when they grant me more speed.
Apologies if this post rubs you up the wrong way, but I don't believe in dressing feedback up - it's constructive, live with it. You've got potential but I don't think you're hard enough on yourself during the production stages to end up with a high enough quality video at the end of it. Clearly you're doing something right, you're nearly on 300 for f**k's sake - but you can definitely do better. You won't get a sub out of me right now but if you take my points on board you might see at least some improvement in subscriber retention. Feel free to tell me I'm wrong, YTT - but 225 subs in under 6 months, I must be doing something right.