You gave a small sample size or questionable contracts which is dwarfed by the amount of times we're all pleasantly surprised to hear the reasonable and sometimes under market value of contracts. Look at Armia, Lehkonen, Petry, Gally, Danault, Chirot etc. How many 30 goals scorers are getting paid $3.75MM? Our highest paid forward is Drouin at $5.5M.
So sorry, disagree with your premise that Bergevin doesn't get good value. In fact, most would take the opposite view given his hardball tactics on Radulov and Markov caused them not to come back.
Markov: Would you rather Markov for 2 years at whatever price he asked, or Alzner? Well, we got Alzner to replace our best LD,who would have probably retired after his contract.
Radulov: Seriously? not signing him was a great demonstration of MB's negotiation skills? Let me doubt that he would cripple our cap space... and be our best forward.
Armia: A 20-30 pts defensive forward making 2.6M. That's not awful but not great.
Lehkonen: Again... 2.4M for a 3rd/4th liner. What's so good?
Petry: Good vision on seeing Petry become as good as he is today. But look at Petry's stats 5-6 years ago though. Not sure if a $33M 6 years contract with a NMC was that hard to negotiate for what he was at the time.
Danault: Pretty good contract. Hopefully he gives us another solid season before he costs 6-7M per year
Gallagher: I'll give him a steal there! He's clearly underpaid for what he brings to the ice and off the ice. I'm afraid of what he will cost next but it's Gally, he's not gonna ask for much right, right?
I don't think Drouin being our highest paid forward a good sign. There simply is no player (Gally?) worth really that much more. This team not having forwards with 8-9M contracts is not MB's genius, it's because there's a lack of talent.
TLDR: Apart from Gally and Danault, I think most of MB's signature were average or bad contracts.