I like it a lot. I wouldn't call it dated: it's a classic and it's consistently in use, but in a cyclical way. Here it's coming down from a peak of top 100 use between the 1960s and 2008, after last making the top 100 in the 1900s. It's still at 263 though, and I think it will stay around.
It was a passed-down name in my family for several generations: the first one was born in 1811. She's
Rachael in some of her data, and so is one of the two Rach(a)els I know. I'd choose the simpler form if I were using it, but
Rachael as a variant has a long history, and I think it's fine.