For me the 90s Wednesday is a valuable addition to the original series, perhaps the only one. She couldn't have existed when it was made. I'm really enjoying the Wednesday series at four episodes in. It's a mystery thing with some nice Tim Burton touches, decent writing, good acting and a sense of humour. Thing gets a starring role and Jenna Ortega settles into the lead nicely. You can't touch the original series and they make no attempt to do that, so it gets an 8 on the Scarfometer (sorry Mo!)
If I look past how neither the humor nor title character makes me want to watch further, there's still the mystery you mentioned or Enid that just happens to be INVIGORATING (not biased at all, that she's also a Sinclair). Anything it borrows that the Harry Potter series utilized nicely is also a good addition. I like the other side characters as well. Most ppl complain about Gomez, but I think Morticia is the one who needs to convince me a bit more. I guess we'll see if I grow to like it despite not being a fan of this Wednesday Addams or as the latin would say: quit, Poe-crow! :)