The first day I would build
Give the city one clear route before adding extras.
- Start with Volga embankment and Kirov Avenue while energy is high.
- Use Radishchev Art Museum as the natural reset instead of crossing town too early.
the easier plan is Kirov Avenue and museum first, Volga embankment afterward, Sokolovaya Gora separately. That keeps the day readable instead of turning every good name into a separate detour.
I would rather leave one place for tomorrow than drag a tired route through Saratov Bridge just because it looked close on a map.