Even in the 80s and 90s they realised - with the style of racing back in those days too - that Valdezcaray is useless in and of itself in creating gaps and isn't well connected enough to any climbs challenging enough to give motivation to attack from, so either put MTTs there or put the finish at Cruz de la Demanda. I believe the road to the latter is in disrepair now, but it was an iconically 90s MTF at the Vuelta.It can be good, but it requires a very big commitment from one rider to just take off already. It's obviously better than Tenda, Valdezcarray and Larra Belagua, but that's a pretty low bar.
That, the Alto de Abantos and the Alto de Redondal near Bembibre and Ponferrada would be good to resurface. Redondal never hosted the Vuelta but it is 9km at nearly 10% and was an MTF in the Vuelta a Castilla y León a few times back in the late 90s and early 00s when that was a strong short stage race. Leonardo Piepoli, Paco Mancebo, Javier Pascual and Juan Miguel Mercado were the winners there and the top 10s of those stages include the likes of Carlos Sastre, Chava Jiménez, Isidro Nozal, Óscar Sevilla, Paco Mancebo, Vladimir Karpets, Aitor Osa, Unai Osa, Levi Leipheimer, Haimar Zubeldia and Georg Totschnig.
Insane to think what Castilla y León once was. Hell, 2010 was a great edition featuring a Morredero MTF - the last time it was raced to a finish at the ski station in fact - as Igor Antón won after he, Ezequiel Mosquera and Juan Mauricio Soler worked together to break Alberto Contador - but couldn't do so by enough to stop him getting the lead back in the ITT the next day. It was a really nice little five day race back then... used to aim for a format of "one sprinty sprint, one punchy uphill sprint, one stage with some obstacles but a flat finish for durable sprinters and/or baroudeurs, one mountaintop finish, one ITT". Now it can't seem to decide between being a worthless flat one day race with a péloton made up of domestic Spanish and Portuguese riders who don't do many sprint stages, a decent one day race with a tough parcours but a very underwhelming startlist, or a 2- or 3-stage race with little of great interest going on.