36 weeks of Jumbo Cactpot playing the same numbers

[Niwashi]

I would probably also change it to match against all 4 of your numbers, not just the last one(s). Same prizes as current.
...
Better(?) suggestion: Since mini still trumps it by so much, buff it further. Give it Mastermind-style matching, and increase the payout.

base pay: 100.
Every perfect match: x10 multiplier
Every soft match (wrong position): x5 multiplier.

I like your first suggestion better. The Mastermind-style is overly complicated when applied to a system that allows duplicates, and gives some numbers a better chance than others. I like the simpler suggestion that just counts the number of matches (by position).

Does your 1st digit match the drawn 1st digit? yes or no
Does your 2nd digit match the drawn 2nd digit? yes or no
Does your 3rd digit match the drawn 3rd digit? yes or no
Does your 4th digit match the drawn 4th digit? yes or no

Count the number of "yes" answers and that's how many matches you got. Just remove the current rule that you have to match the fourth digit before it will even look at the third and so on.

Current:
0 match: 89%

That's 90%