The 1974-75 Topps set has a great design, with the team name in big letters going along the right side of the card and the player position written inside a basketball down the bottom. It was such a good design that Topps repeated it decades later, for 2001-02 Topps Heritage. The more recent set has rookie cards of a versatile and title-winning center, Paul Gasol, as well as a high-volume scorer, Joe Johnson, and the 1974-75 Topps set has similar cards.
On just his college statistics his rookie card should be worth a lot, and despite missing plenty of NBA games with various foot injuries Bill Walton would win two NBA titles. His rookie card is wanted by Portland, Boston and UCLA fans as well as those who have enjoyed his basketball commentary. When he led Portland to the 1977 title, Walton was not only a double-double machine with 18 points and 15 rebounds in the playoffs but had 5.5 assists per game from the center position. He was the NBA's top Sixth Man in 1985-86, when he played a career-high 80 games for the season as the Celtics won the title. Walton's rookie card varies in price depending on condition with near mint-mint graded examples stretching over $200. However, you can find a nice, ungraded example on eBay for around $75 or even less.
The other rookie card that collectors look for from that year is George Gervin. If Walton was a player with a variety of skills then "The Iceman" was someone with one real talent, Gervin could score like few others. For his two years of college basketball he averaged 26.8 points. In four ABA seasons he would average 21.9 points. He led the NBA in scoring four times, and over his career he averaged 26.2 points. Gervin also scored 33 points in one quarter, it was during the last game of the season as he battled for the league scoring title. Even after his NBA career ended Gervin still had more scoring to do, he went to Italy in 1986-87 and averaged 26.1 points. A near mint-mint PSA 8 will run about $100.
The 1974-75 Topps set had other rookies to consider, including those of George Karl and Doug Collins. They are more famous now for coaching than for their playing careers.
A complete set, all cards ungraded except for a Wilt Chamberlain that was graded PSA NM-MT 8, sold on eBay for $349 in the fall of 2012. Another complete set sold for $275.