I would offer 6 years, $90 million.
Year 1 $10 mil (Age 38 season)
Year 1 $10 mil (Age 39 season)
Year 1 $10 mil (Age 40 season)
Year 1 $10 mil (Age 41 season)
Year 1 $25 mil (Age 42 season)
Year 1 $25 mil (Age 43 season)
I am batting .500 with contracts like this. I have had 3 accepted.
The first (Columbus "HGH" Bumpus) played out ok. The player lasted until the 1st salary increase but put up a low 3.00 ERA that season and then retired. He pitched until he was 42.
The second ("King" Rupert Salomon) played until the same salary increase but had deteriorated drastically and received a CEI that ST. He rode out the season on the DL and retired. He was 38 when he retired and was only 3 years into the contract.
The third is still active (Richard "The Mechanic" Honea), I had to have one nickname that referenced Charles Bronson

. We shall see how it plays out.
Sorry, I cannot get the links to work properly. If you are interested they are in our league history. I cannot get the player pages to link, only the History main page.
All three can be found in Players tab in our
League History, I am pissed that I cannot get the stupid links to work right. All three players are in the first 5 listed on the "Alphabet" page of the players tab.
Good luck,
Tom