I was considering the $33 monthly plan, now I am considering leaving Koodo.
They have been steadily increasing prices (and my employer doesn't give anyone raises).
Personally, I find that only Wind offers really great plans at 40$ with everything unlimited, only downside to it is that most of Canada outside of major hubs is "roaming"
I take it that you do not like your current plan - when you look at your usage are you going over on anything? And if so, by how much - the best thing to do is to look at the past 3-6 months in selfserve to determine how much you use your phone...this will at least give you a guide of how much you use the phone, and help determine what sort of plan you should get ( whether you decide to leave Koodo, stay with your current plan, or change to a slightly more expensive plan).
There have been times where I went over by a few minutes, but one month where my family was having problems so I ended up using a lot of minutes in one month (this is why I suggest looking at several months worth of bills, so you get your average instead of looking at last months bill and thinking "OMG, I went over by 200 min, I need to change my plan").
Although I cannot convince you to stay, what I would say is to look at all plans of places that you are interested in (Wind, Bell, Rogers, etc...) to decide. At the same time, look at the coverage that they have in places that you would be calling from - as Mathieu said, Wind has a plan that you may like, but they usually only cover metro areas, so you may have no service in an area that you are in a lot of the time, or be roaming. Most (if not all) companies will give you a guide to their coverage.
If you do decide to switch to another company, you will want to get your phone unlocked first, so it can be used with that company, plus you will probably want to port your number (move it with you to the other company).
I noticed the increases too, was not impressed. FIDO and Virgin plans are still $2 cheaper....However, FIDO doesn't include international SMS/MMS or voicemail any more and Virgin in only offering MMS to Canada and US only for a limited time (no videos) Where KOOOD is still offering unltd SMS/MMS worldwide (sent from Canada). So your choice! See what you need and then chose the plan that best suits you.