Tkachuk would scare me. While he's only 25 next season, he's coming off a career year with a 3.25 pp/60, next highest season was 2.27 three years ago - how much is maturity, how much is a fluke fed by JG having his career year. They committed a lot of money to a guy who might be no more than a 1LW/2LW.
Huberdeau is also coming off a career year, but has a better track record the last few years. But he's four years older.
With Huberdeau and Weegar and a 1st, Calgary has more options, they can see if they can work out a reasonable extension, move them at the TDL or let them walk after the season if they're a legitimate playoff contender. Tkachuk made it clear he wasn't signing there.