What are you expecting? I'm not saying Tanev is old, but he will be 27 in November, his contract takes him to 31 years old (which in a vaccuum could be seen as a positive), but there is a risk his game takes a nosedive since he does not produce offensively (which is OK, but he needs to have very good defense for a long time to come if he doesn't produce offensively).
As a rangers fan, I offered a top 6 winger, a top 9 center, and a draft pick for Tanev and a better draft pick. That's pretty good for a top 4 shutdown defenseman, and about as close as you'll get to a Hall for Larsson swap. Kreider is a top 6 winger NOW, even if he tops out as a 50-55 point guy.
Unfortunately, I can't see Tanev bringing in Trouba (like some others stated) unless you add another high profile prospect like Virtanen--Winnipeg's GM is cheap and doesn't like to trade picks, just players, and he likes to rip people off (Benning might actually be his target, lol)