I'm thinking about writing a guide for Kenshin. I don't think I've had this much fun with a lead since I started playing. Seeing giant numbers is awesome and the team flexibility is great. Obviously the downsides are active reliance and general glass cannon problems. Most teams I've put together are also criminally short on skill boosts and have trouble hitting 6 combos while doing meaningful damage. Two crosses plus 4 more combos isn't a trivial task.
For any serious content you need three things minimum:
1) Bind Clear
2) Shield
3) Full board change
Kenshin's not bind immune so naturally you need something to clear those binds. I'm not a big fan of heart row bind clearing on this team since there's no bulk to take a follow up hit. You really do need an active bind clear solution for the most dangerous content.
The common theme with Kenshin (and Saito to a lesser extent) is how fragile they are compared to the top leads. For any serious business content you need a shield to survive vicious preemptive attacks, stall for a skill, or skip dealing with a 99% gravity.
Finally, you need a way to guarantee at least 2 crosses while also removing junk from the board. A full board change is a one button solution to both problems. Yes it's possible to get supremely trolled and only end up with 3 fire or lights but Kenshin's active can fix that. His cooldown is short enough and he has plenty of hastes in his optimal teams to pretty much guarantee uptime.
Time extends and the like (CTW) are also nice. You don't need to worry about rows or TPAs since crosses don't trigger either it's Orb Enhance all the way.
Board change and shield options are easy: Saria, Kiriko Another, Superman, Ilm (not a great choice). Shields are Indra, Valen, Wedding Izanami (secret best shield IMO), or inherit something like Susano.
Bind clearing is something I'm having trouble with. Gadius is the obvious choice since he makes a friendly board, is unbindable and can clear. but since it requires a heart row there's no guarantee you survive the following hit after a bind. He's still a good sub and if you enter a dungeon where a bind isn't followed up by a fuck you attack it's ok but that's not always the case. On type there's Red Riding Hood, Attackerasu, and slightly off type is Lmeta, Awoken ama, and Sakuya. There's also the dragon knights with their bind clearing heart breaks. I'm not sure who fits best here. You can always put Lmeta/dragon knight on Gadius I suppose but that's risky given how few SBs the team tends to run with.
With those pieces covered it's a matter of filler. Terra from the FF collab is a great inherit skill on Kenshin since it's a guaranteed x324 on the board. Tsubaki brings a ton of OE to the table a useful active with a haste to get Kenshin and Wiza up faster.
So for me a solid general purpose Kenshin team would look like:
Kenshin (Terra Inherit)
Awoken Indra (haste, and shorter cooldown makes it worth losing a turn of shielding vs other evos)
Saria/Kiriko Another (with the other inherited for insurance)
Gadius (Fire Dragon Knight inherit)
Tsubaki
Kenshin
With this setup you have enough SB to get Kenshin up turn 1, potentially 4 hastes (Kiriko means 3), solutions to Kenshin's biggest weaknesses and enough damage output to choke 297 Zeus. I don't expect to see him clear Arena 3 or Mech Zeus but I think everything else is doable (even if not consistently) by him.