Yes, you are mistaken.
Chicago II is a great album. What you are calling "Colour My World" is simply one movement of several from a masterpiece Rock classic musical suite known as "Ballet for a Girl from Buchannon" -- written by trombonist and composer James Pankow. [For radio airplay -- two movements from the Ballet were chopped into singles, "Make Me Smile" and Colour My World -- both Top 10 singles.] Chicago generally plays the entire suite in its live concerts these days even though it was too long for radio.
Other notable songs on that album include a little song that you may have heard of known as "25 or 6 to 4", also a Top 10 single -- they played that song at their Rock and Roll HOF induction.
Other memorable songs on that album that still hold up pretty well are "Wake Up Sunshine" written and sung by Robert Lamm and "In the Country" written and sung by the late, great Terry Kath. These last two didn't get much radio play since, between the two albums, there were already enough popular Chicago singles out there to fill out most any radio station's programming list.
Agree that all the political stuff on the album doesn't hold up all of that well over 50 years later.
YMMV.