Planning a fall trip to both Barcelona and Portugal.

Here is my current draft itinerary:

Landing in BCN late afternoon Fri, Sep 2

3 days in BCN (Friday, Sep 2-Sunday, Sep 4)
Depart BCN mid day Monday, Sep 5

3 days in Lisbon (Monday, Sep 5-Wed, Sep 7)
1 day day-trip to Sintra (Thursday, Sep 8)
Depart LIS early Friday morning, Friday, Sep 9

3 days in Algarve (Faro) (Friday, Sep 9-Sunday, Sep 11)
Depart Algarve mid day Monday, Sep 12

I've been to BCN once before last year in April and loved it, which is why I'm trying to see it again on this trip. Mostly to eat lol! And maybe enjoy some night life this time? But I have never been to Portugal before and I wanted to get in a nice beach in Portugal. I'm also open to doing a closer beach to Lisbon (Comporta??).

I don't have a ton of must sees in either BCN (since I've been before) or Lisbon besides the day trip to Sintra (but I'm open to suggestions!). So I was thinking this trip wouldn't feel 'too' hectic/rushed...would others agree?