Within 20-25km per day I would suggest
- 25,2 to Tres Cantos,
- 25,3 to manzanares el Real (possible intermediate stay after 10,5 km in Colmenar Viejo),
- 23,5 to Cercedilla if you choose to stay in albergue juvenil at Las Dehesas approx.3km outside the town but still on Camino (possible intermediate stay in Mataelpino, which is 18,1 km from Colmenar Viejo),
- 27,3 from Las Dehesas/Cercedilla directly to Segovia or 22,5 option via La granja de San Ildefonso (and next day short 12,2 km to Segovia),
- 21,5 to Ane (intermediate stops in Zamarramala after just 3,2km or Los Huertos 12,8km after Segovia)
- 24,6 to Nava de la Asuncion (intermediate stop in Sta.Maria la Real de Nieva after 11,8km)
Then it gets a bit tricky, well depends on the previous stages:
- 9,4 to Coca, 16,1 to Villeguillo or 33,4 to Alcazaren. I did it in two stages, to Villeguillo and next day to Alcazaren and enjoyed it thoroughly,
- 24,9 to Puente Duero.
I know
@peregrina2000 would suggest 13km detour to Valladolid from Puente Duero
but if you continue straight on the Camino then:
- 27,4 to Penaflor de Hornija (intermediate stop after 12,7km in Cigunuela),
- 24,3 to Medina de Rioseco (or 23,7 from Cigunuela to Castromonte which I would suggest if you take detour walking to Valladolid and back to Camino),
- 25,3 to Cuenca de Campos but I think I walked slightly different route than Gronze has it and it might be slightly shorter and more important nicer,
- 21,6 to Santervas de Campos (intermediate stop in Villalon de Campos but only 5,4km after Cuenca so it would be more than 30km of flat terrain from Cuenca),
- 19,2 to Sahagun although I stopped in Grajal de Campos (which is by Gronze 29,8km from Villalon but I can guarantee it's less because I came from Villalon to Santervas so early that I decided to push on to Grajal). And there is only 5,6km from Grajal to Sahagun so you don't have to make it your stage end
Anyway after Segovia you have quite a lot of wiggle room for different, longer or shorter stages.
It's beautiful Camino especially if you like Tierra de Campos aka Meseta. Go for it!