Someone posted the idea of having a bottom 10 teams gunning for #1 overall pick rather than 5 teams that just missed the playoffs by a few points. I agree for one following reason: late March/early April is their "playoffs" in late stage of regular season and gaining experience out from it and learning not to have a slow start next season or have a weak finish due to collapse and injuries woes. Bottom 10 teams most often don't have anything to play for except for their pride and GM secretly hoping for tanking. So I would do two things to prevent tanking and improve lottery system:
First of all, I would weight odd heavily to top 5 and small percent to rest of bottom 10. Should 15th place teams won the lottery, they might gain 10 spots to 5th spot and I see that it would be a fair system, they get a good prospect out from it, rather than the top prospect. I call it, leap 10 spots lottery system. I think that all teams should participate in the lottery, giving the president trophy team a chance to leapfrog up to 10 spots and if they wont he lottery, they would end up 21st pick. That should take place shortly before start of the playoffs. That way, the president trophy teams don't have to gut their teams due to lack of good prospects after their peak and maintain their place in hockey rather than collapse that fast like Canucks did. I feel that 10 spots up, rather than the usual 5 spots would be a good compromise so that the worst team of the whole hockey get its 2nd spot rather than 4th spot.
I would suggest, the worst team of each conference get its equal weighted odd with other worst team in their respective conference due to different schedule matrix. With that in mind, I would like to add a twist to who gets its first overall pick if a team won and leaped 10spots but don't land first overall pick. The teams with the best head to head match-up between two worst teams get its first dib should one of them don't win the lottery into the 1st spot and other get its 2nd spot. That way, the teams will have to win their match-up in the regular season and will make every games count when it comes to non-conference match-up. It's a compromise and much better than the top 3 lottery system. It is possible for 2nd worst team in the league but worst in the conference to hold a first overall due to the winning record without winning a lottery if president trophy won its lottery and landed 21st spot and the worst team in the league picks 2nd. That way, nobody will know who win the first overall pick or their drafting order until end of the season all the way to teams that missed the playoffs. Rather than following the points percent, it would alternate the conference back and forth.
Example: Nobody in bottom 10 teams won the lottery, final conference standing. Rather than using 2019/2020, I will use 2018-19 season as an example. Worst team in Eastern Conference: Ottawa Worst team in Western Conference:: LA.
Head to head match-up.
First game: Ottawa 5 LA 1
Second game: Ottawa 4 LA 1.
Ottawa wins season series 2-0. Ottawa get its first dib for first overall pick with both teams finished the worst in the conference in 2018-19 season. If someone in top 10 wins the lottery, Ottawa get 2nd pick and LA get 3rd pick. LA had a better season record than Ottawa.
Now, who get its 3rd and fourth priority in the drafting order? Again, use the head to head match-up and whoever wins the season series get slots in the priority. You repeat those process alternative between East/West conference on their final conference standing and head to head all the way to 15th spot. This way, every games is meaningful against games between worst team in the conference despite being hapless against the stronger teams over the long season. This is a fixed
Trade deadlines must be moved up to after New Year's Day, rather than last 6 weeks of regular season to prevent tanking. Trades may be allowed after the deadlines but they would not be eligible for the playoffs. Trade may be used to shore up their injury woes late in the season. Teams will see no point of tanking for a more than half of their season if they traded away their stars on the worst team in the league. No other team might be willing to pay a hefty price unless they are nearing the playoffs and see where they stand 6 weeks left and might be willing to gamble by buying to booster their chance for Stanley Cup.
This is how you fix the tanking through trades by moving up dates and no guarantee that you would be losing games and get it's better drafting position due to head to head match-up.