Hockey team plays in a standalone hockey league, the NCHC. And lacrosse plays in the Big East. So moving the bulk of sports, including basketball, from the Summit to WCC would probably have no effect. They made the NIT in recent memory and it seems like the money and facilities are fine.
They have won 9 hockey championships, 1 in lacrosse and 24 more in skiing. Which puts them pretty high on the all time list.
That success continues into the present. Their hoops team has historically had a bad run, but I believe they used to play NCAA DII for most or all sports, with Hockey as a D1 sport - so they just don’t have that history of most WCC schools.
Without delving into NCAA minutiae too deeply, a similar exemption still exists for DIII teams to elevate one men’s and women’s team to D1 (see, for example, Colorado College and their hockey and women’s soccer program). The previous reverse-uno maneuver was to play all sports at Division 1, but Football at Division 2 - this was how SCU and SMC played football from '60s or so into the early '90s. When the NCAA forced schools to move their football teams up, SCU elected not too due to the extreme cost; SMC tried to and persisted for some time. USD, incidentally, continues with football as a “D1” program without scholarships with a weird cadre of like-minded schools, including Davidson all the way in North Carolina.
Speaking of weird cadres of schools, look up the current composition of the Summit League, where DU plays hoops now. It is very strange and not a good institutional fit. WCC would be much better, and I would love it as I live down the street. Denver is a big market (which fits the WCC profile of a small school in a big city) that we don’t currently have a footprint in, a basketball city, and the state has solidly supported both CU and CSU, who are both bubble teams this year.
Long, long story short, amongst the options, I think DU would be a good fit but the venn diagram of their sports vs. WCC sponsored sports may be incongruent.
A final counterpoint - Pacific seemed to have way more success as the only private school in the Big West. That was probably a big part of their recruiting pitch. Moving them into the WCC, they went from being the only private school to one among nine, with the worst location. And last night showed they’ve got some deep issues in Stockton. So grass isn’t always greener for someone in DU’s position.