I looked at that cruisetour on HAL's website, and I see what you mean. Hard to get any info there. It does look to me like you'll have a full day at Denali, so you'll want to get as far into the park as possible.
We're not Denali experts, but we've gone there on two separate trips. We took the park shuttle, rather than an organized tour. It's not plush, think "old school bus" and the amount of narration you get is entirely dependent on the driver. One driver was wonderful. He was an older guy, who had a wealth of information to share. And he shared. He also would stop anytime somebody called out to him to do so. Another driver wasn't good at all. No narration at all (we didn't mind that) and he just wouldn't stop for long anywhere. I would still do this shuttle rather than one of the tours, since it's cheap enough to book the full trip but still have the flexibility to bail out at one of the rest stops and catch a different shuttle back if you feel like it. Bus Fares And Destinations In Denali National Park (denali101.com)