Sure
I never thought about Kellan much, so could be interesting thought exercise.
I agree with you about fast mana. I don't think you need it, not unless you are pushing for really fast games. I went that way because of Avacyn's CMC, and to get ahead of control decks (used to play against them often), but Kellan is low CMC and a tutor in the command zone, which provides plenty of opportunity for consistent ramp. I see you already got Sword of the Animist, and the Dowsing Dagger.
I think the Dagger would be my go to play because it curves out nicely: turn 2 tutor, turn 3 Kellan, turn 4 attack with the Dagger and hopefully flip it while causing 8 commander damage, not a bad deal. The Sword has the same line of play, but less damage and take longer to make the same amount of mana.
I definitely would replace the sacrifice package, it doesn't fit with Kellan at all. Sunforger is probably where I'd focus my lines of play with Kellan, because it should be consistent with his tutor ability. I find the transform boardwipe useful to clear our blockers, but again, with tutor in the command zone, so easy to find evasion. I would probably look at some Auras, like
Spirit Mantle, to make him unblockable, which would double up as good blocker if you can give him vigilance.
Trailblazer's Boots is not a bad choice, but it is conditional (even if most games will have nonbasic lands). I think because you have the tutor always available, you should be okay with just finding the right Mirran Sword to get protection from whatever colour blockers your target opponent is using. That way you get the evasion you want, plus value from the Sword, rather than wasting mana on the Boots just to be unblockable.
Sanctum of Eternity could be decent land to include, and other effects that bounce Kellan to your hand to re-cast the tutor without doing it from the command zone.
I'd probably look for Equipment, or other hands, that make tokens in some easy and consistent way, to lean more into his second ability. Even 1/1 Spirits can be dangerous when they get +3 or more power, and that should be easily enough to do. That way you could deal with one opponent with commander damage, and another with regular damage. Top of my head there is
Felidar Retreat, triggering on landfall to make 2/2 Cats.
Overall, I'd say with Kellan my primary strategy would be Sunforger, followed by making tokens and buff their power. The main risk with this kind of deck that comes to mind is the amount of tutoring you might end up doing, that could get boring.
Oh and I'd include
Inventory Management. I haven't had a chance to test it out yet but it is a bonkers card for Equipment/Auras Voltron decks.