IMO the buffs are a good step in the right direction but are just not enough atm.
Let's start with the stim 40% whilst just sprinting is just too slow and feels like it's just Respawn saying here Octane is the fastest legend now but he's just not fast enough atm. However, if they keep Stim Healing in the game and don't patch it I think this speed can be worked with if the stim duration is increased or the health cost is reduced/removed or if swift mend healing is increased.
That leads to the second problem. Octane still feels like he has no passive. It honestly feels like swift mend is just a part of his tac, which IMO you can't even use that much since you don't want to be running around with 0 health. A better change by Respawn would be to make his passive so that his base movement speed would be higher and then revert stim back to its original value. Also, they could make stim's cooldown longer but REMOVE the health cost. It just doesn't make sense to have a tac which hurts you so much to use. It just makes it too situational.
Finally the jump pad. While I would have preferred them to work like the Geysers on Worlds edge, I'm quite happy with the changes. With a 60 sec cooldown and the utility and they provide, they're pretty good, although one change I'd make is allowing the double jump to fully change the momentum of the first jump so you can actually fully change direction without slowing down so much that you become an easy target. Still, I'm pretty happy with the first steps.
However, considering how game-changing the lifeline revenant and even mirage changes are I am kinda disappointed that this is what respawn has for octane and am hoping there's more to come.
Edit: Made a mistake on Jump Pad cool down.
Source: https://www.reddit.com/r/apexlegends/comments/hfajjq/my_thoughts_on_the_octane_buffs/