Porto to Lisbon over 5D/4N by bus
 

I was originally thinking to drive one way from Porto to Lisbon over 5D/4N. I am now looking at the possibility of doing this by bus/train. I was wondering if you had any suggestions on this matter? I have read there are not many buses running to the smaller towns on the weekend which could be an issue.
I was thinking something like the following:
Day 5: Fr Apr 13 (Port to Coimbra, night Coimbra)
Roman Ruins of Conimbriga and Coimbra
Day 6: Sa Apr 14 (Coimbra to Tomar, sleep Tomar)
Drop luggage at hotel first then Almourol Castle.
Day 7: Su Apr 15 (Tomar to Obidos, night Obidos)
Tomar to Batalha and Alcobaca Monasteries back to tomar then to Obidos.
Backtracking I know but only way I can see to deal with luggage.
Day 8: Mo Apr 16 (Obidos to Evora, night Evora)
Obidos in the morning and travel bus/train to Evora
Day 9: Tu Apr 17 (Evora to Lisbon, night Lisbon)
Evora in the morning, late afternoon train to Lisbon