The ending was great.
Sakuragi settling the score with Rukawa and the haruko love story.
I think, sakuragi is better than rukawa because he has athleticism and the fact he could learn basket ball for 4 or 6 months. Sakuragi has higher ceiling than rukawa IMO. So it's up to the mangaka to show it or not, since slamdunk is a rival sport manga.
The love triangle really like naruto love triangle. The difference is it doesn't solved. There are many factor:
1. The setting of sd is on the modern, highschool, and non fantasy world. So pairing doesn't necessary need to happen. Usually pairing happen in shonen manga to show the little kid or if the manga focus more on the romance like romcom genre.
2. The author keep the status quo until the end of manga. Which naruto follow it.
3. In the end, sakuragi confess that he love basket ball, since he join his club because of haruko.
In sport manga, romance happen between status quo or canon pairing only to for short time and then break up leading the mc doesn't has love life thus focus on sport aspect.