Unfortunately I haven't played my Sylvaneth that much since the Covid thing started. But I still like Alarielle's summoning feature and I am happy to spend ~200pts more in her point cost. Even if not all of the summable units are worth 200pts it gives you a lot of flexibility based situations in game, e.g. do I need Kurnoths with bows/swords/scythes, a tree lord, reventants...
As they will come at the end of the movement phase you can even get them in a better position if alarielle moved full 16inch (in theory).
I am always happy to spend those 200points extra, rather than being bound to a specific unit with the start of the game.
However I also think 740 is a bit too much, based on the missing protection against MW no matter how good the healing is.
A +1 to cast would also have been great, at least close to Wyldwoods. E.g. why can a warsong reventant cast a spells easier than her goodness 😄