It would be nice if the proc area for multistrike was a bit greater. Because the proc distance is calculated from the center of an enemy, on the biggest bosses, multistrike cannot proc at all (Lagon is an extreme example, but it is also really hard to proc on some other big enemies, like in the general Harton + Spymaster Zerrick fight).
I think it’s okay to have to invest in the area node and position yourself properly to be able to proc it on bigger enemies; it compensate faster/easier casting with being closer to the ennemy and harder positionning, but I think the area node should have bigger increments, and when fully invested in should make it possible / easier to proc on the biggest bosses (I guess Lagon is an exception and it would be better to rethink where its “center” is.)