I think Talia al Ghul from Arrow and Barbara from Gotham would also work 

Honestly, it would be more interesting to me if Kate’s disappearance leads to a reformed Alice who takes on a mentor role for this new Batwoman. I’d like to see that dynamic play out more than I’d like to see Kate recast.

Yep, we already have Pennyworth who was British Intelligence.

So Stargirl is going to recruit not just a new Wildcat and Hourman to her teenie-bopper JSA, but also a new Green Lantern?? And maybe Dr Fate?? Yes please

The new Batwoman could possibly be Helena Wayne, the daughter of Catwoman and Batman, who is usually Huntress, but was Batwoman on at least one alternate earth

Have Rachel Skarsten play a dual role. Alice and Batwoman (It’s the CW, it doesn’t have to make sense. Something, something multiverse, or maybe clone).

“Not to mention Batwoman’s Bruce Wayne has been “missing” for years...now Kate Kane will mysteriously go missing too?”

If they’re smart about it, this could actually be a pretty good plot hook. What the hell did Batwoman discover about Bruce that made her also disappear? 

Huh. On a previous article about this I wondered if they were going to Darren her or Doctor her, and it looks like they’re just going to Frank Burns her.

Seriously they missed a golden opportunity to blame Barry as to why Kate looks different.