I strongly disagree with the idea of going back to 2005-06 penalty standards. There were way too many penalties being called then. Now, maybe slightly more could be called now than what is being called, but please not a lot. I personally think it's a good thing that the game is 'cleaner' now and that players know the limits of what is legal and what isn't, and don't cross that line every 5 seconds as in, say, the early 1990s.
Penalties and special-teams in general are always going to be key in hockey, but they shouldn't be 'depended' on to increase excitement and/or scoring. People who say the officiating now is the worst it's ever been obviously didn't watch hockey before about 2000.
For me, what increases excitement is creative play and a mix of strategy/'systems' hockey with risk-taking hockey. I mean, what is more exciting than watching great players take risks on the ice? That's the peak of excitement. If a goalie comes way out of the net to chase down a puck, or if 4 players (including a D) carry the puck way down low to the other team's goal-line, etc. -- that's very exciting. If a player throws a body-check at the other team's top guy, it's also really exciting because it is risky behavior in terms of the violent response you then expect.
Calling a bunch of penalties IS NOT going to make any of these things happen. If anything, it's likely to increase boring hockey. Goal-scoring will slightly increase, of course (which is good), but more penalties likely means more system-strategizing to kill penalties and fewer occurrences of the most-talented players on the ice.
Because of improvements in goaltending equipment, every goalie now plays a no-risk style. They know the most efficient way to keep their million-dollar job is to slide horizontally across the crease, and never leave the net. No risk = boring.
Because of conservative no-risk coaching and the loser-point system, skaters don't want to take too many offensive chances. Defencemen hang back and clog up the middle. No risk = boring.
Because the NHLPA is now way stronger than team-culture, nobody wants to throw risky checks at good players or hit a goalie, etc. No risk = boring.
So, limiting shot-blocking (if that's even possible) and limiting equipment is all well and good and should be considered, but to me the real problem with NHL hockey now is that it's all NO RISK. That's simply boring.
The League "brain"trust should be focused on finding ways to encourage teams to take more risks.