I personally think the character relationships between Max and Misty developing (since there were a very select few encounters beforehand) was very nice. However, I definitely liked the care that May had, and so the sibling relationship I thought made the episode rather worthwhile.
In terms of battling, I think the first Mt. Moon episode was significantly better in terms of battle mechanics alone (size doesn't matter, counterattacks, use of digging, zubat's hate of lights, seymour, discovery, etc).
Thus the character composition I thought was much better. Max has been separated from his sister before, but not very often (I can recall one separation with Brock, but I can't remember too many other times). And so, Misty presenting a different mindset is nice, since it is another character aspect.
Also, in the dub, Max refers to his sister as May most of the time, so it doesn't have as much as a sibling feel. As opposed to the raw where Max virtually always calls his sister as ... sister lol (him saying Haruka would sound odd because her name means far, and they're supposed to be close, so far and close would seem contradictory). Of course, this separation was nothing like the Donphan separation because this one had an explosion as well as falling off a cliff (DE was "run away from trampling rolling Donphan") not to mention it was raining and they had to use a tree as shelter.
Thus I think the importance of the sibling care (it's more like re-emphasized, rather than adding something that wasn't there, because clearly it was already there). Another aspect I like about Haruka's character would be the watching over of her little brother (which doesn't occur for any character except for Brock, but this discludes travelling. Since Misty is the youngest of her siblings and Ash seems to be an only child, it doesn't occur for them. This might be another reason why the writers had May have a little brother in terms of anime storyline ... but I think Max was in the games for like 5 minutes in the beginning but I forget anyways, since roles are totally different.)
Cleffa was okay. At least they introduced it without having it being super powerful against team rocket. A Clefairy family team all using metronome with Gonbe seems much more reasonable than that single Cleffa doing the same thing alone. Solarbeam was rather boring though. Their explosion back in Kanto was more entertaining xD
