As a whole, gameplay is decently fine, but
You're criminally underutilizing a lot of your defensives. That's fine in 12s, especially with the ilvl bump, but it can be very rough in coming key levels where proper defensive use is more important. You only pressed Spell Reflect 8 times, for example. You didn't even use it at all in the first boss fight, when it is a resource free, just able to be sent CD to help reduce the damage coming in from Divine Judgment. It's important to remember that it comes with a very nice magic DR attached to it; you can do more with it than just reflect spells aimed at you.
You also only used Last Stand one, and Spell Block only twice at all. I know Last Stand isn't really that good, but it's a defensive you can use. You almost might as well have just sent it on CD with no thoughts and been a lot better off.
The other main thing to adjust is what you're sending outbursts on. You're currently sending almost half and half between Shield Slam and Thunder Clap, which is really rough. You never really want to send Outburst on Thunder Clap as Mountain Thane, which actually has damage modifiers for Thunder Clap. And as Colossus, well, that hurts even more. Shield Slam outbursts will do more damage in AOE outside of truly outrageous numbers, and it always gives more rage, so you want to send every Outburst possible on Shield Slam. Even when playing Thane, it's better to gamble for a few resets by pressing Revenge to see if you can send Outburst on SS over TC. You'll get more rage to cycle, meaning lower CDs and higher numbers of IP pumps.
As an aside, overprioritizing TC in AOE can cause you to lose out on Demolish casts; that's not only less damage, but Demolish also gives DR out when used. Granted, it's only 10%, but that's 10% in addition to Demo Shout. So Thunderlord may not always be a survival increase over time for Colo as compared to getting more demolishes off by abusing the CDR when Revenge hitting 3 or more mobs. Colo also doesn't clap as often as Thane, so it just gets less CDR overall as compared to Thane, particularly since Colo doesn't run Unstoppable Force, the main source of the large amount of clapping Thane does. The main use of TL is to try and better fit Demo Shout casts for CD rotations, which is generally a very case-by-case scenario. It can be useful, but it's best to have a plan for using it imo. That point, if you wanted something survival wise, would likely be better spent on Disrupting Shout, since it helps you keep the party alive and enables you to leverage more utility than usual.
hardy chasm
amber pivot