Sacrosanct
Legend
your example is only good for one or two rounds, before you're out of resources. If you go monk 4 compared to a straight 11th level monk, you only have 4 ki. you also only have wildshape twice. So yeah, you can nova pretty good. But you'll be behind everyone else for most of the combat scenarios. Just like any other class was designed to have really good nova damage.
And then you have the issue of pure ridiculousness. For one, you're ignoring the multiclass rules if you have a Barb 1, Cleric 1, Fighter 6, Monk 1 since you have to meet certain requirements before multiclassing into each class, and odds are you won't have the stats for all of those. And if you did, they wouldn't be anywhere near 18 or 20 since you had to spread them out and thus your bonuses would be less than a straight class. But more importantly, most tables have to have some sort of in game logic to multiclassing. A barbarian/druid is pretty plausible since they could have the same background. A PC with 5 classes? Yeah, that doesn't make any sense.
And then you have the issue of pure ridiculousness. For one, you're ignoring the multiclass rules if you have a Barb 1, Cleric 1, Fighter 6, Monk 1 since you have to meet certain requirements before multiclassing into each class, and odds are you won't have the stats for all of those. And if you did, they wouldn't be anywhere near 18 or 20 since you had to spread them out and thus your bonuses would be less than a straight class. But more importantly, most tables have to have some sort of in game logic to multiclassing. A barbarian/druid is pretty plausible since they could have the same background. A PC with 5 classes? Yeah, that doesn't make any sense.