JVR seems to be consistently valued lower than similar players but keeps producing like a first line player. I would hold onto him to see if Matthews inflates his numbers then sell on a higher note if you want return for him, or just re-sign
JVR still has a slightly higher career goals/game and a better points per game than Jenner, including last season (JVR's numbers are WAY better if you exclude last season). Watch some highlights of the two and you'll notice very different games stylistically - JVR went 2nd overall because he's incredibly talented and his highlights will show that, Jenner is a mule and scores ugly ALOT. He had a huge bump in production last year and leafs (then Columbus, ironically) have been bitten very recently by buying high on guys who breached the 30 goal mark by banging and crashing, see David Clarkson. Could Jenner repeat and turn into a perennial 30 goal scorer ? sure...could last season be the high water mark of a good 3rd line career, also yes. Personally I keep JVR because he proved he can produce without help last year, and there's a ton of help on the way that could bump his production towards top 20 in the league, then the leafs have lots of trade options that bring back real value...and if his output stays the same, he's still a great top 6 piece
Werenski vs. Nylander is very difficult to make a case for either way, any where that ranks prospects has both in the 5-12 range, trying to objectively say that one is much better than the other at this point is just homerism, they both have huge value.