Not sure we've been watching the same team if this is what you think she does, from where I sit she's the only one in midfield who can be trusted to be
given the ball under pressure, in tight spaces, and keep it going rather than being dispossessed. Weir can do it on her day but hasn't been as consistent this season and likes to go for a dribble anyway which is more risky, Losada has the technique but not the agility, and Stanway falls over. The likes of Coombs etc aren't on the same level and it shows when they try to cover for her.
I'm not sure what more you're looking for in terms of moving forward when
she's playing at the base of midfield distributing it to virtually everyone (backwards, sideways and forward) from deep and getting assists. It'd be like criticising Fernandinho for not making KDB-style passes a few years ago or pumping it forward, it's just not part of the job. If they wanted to replace her, they'd either need to change style massively or throw money at someone like Lia Waelti.
I don't entirely disagree with you about tempo being an issue fwiw, but that's that's a team issue, not a Walsh issue, - Alanna Kennedy passing it between herself and Alex Greenwood, the wingers refusing to hit crosses early, strikers holding up the ball rather than facing goal etc. That's where the coaching comes in though, we've never had a top coach and it shows.