Here's my two cents.
What if you could unlock different difficult settings? To get the basic ending you just have to beat the game on the lowest difficulty, but on higher difficulties, it's more challenging, but there are also more scenes!
For instance:
easy - kissing, tit sucking, blowjob, doggy, cum on ass
Medium - kissing, *groping*, tit sucking, blowjob, *missionary*, doggy, jerk off/facial
Hard - kissing, groping, *fingering*, tit sucking, *boob job*, blowjob, missionary, *downward thrust sex*, doggy, *carrying position sex*, jerk off/facial
Expert - kissing, groping, *hand under shirt*, fingering, tit sucking, boob job, blowjob, missionary, downward thrust, doggy, carrying sex, bicycle position sex, jerk off/facial, *fuck her face while she lays down and fingers herself*, *reverse cowgirl/creampie*
People are finding ways of "cheesing" the game. Like memorizing the pattern or taking advantage of always having 2 rounds before the husband comes back. These can both be ironed out. The pattern can be random, or there can be sets of different patterns that can be randomly chosen at the beginning. The husband can have a shorter Grace period but in order for it to be fair, there has to be some way of telegraphing this. Perhaps some of the husband's scripts indicate there is less time, or perhaps there is some difference in the sex scene.
Finally, I think there needs to be more incentive to use the 'check husband' option. Here are some ideas. Perhaps there is an alertness system. If you have sex without checking the husband or if when you check the husband is 'coming soon' then you and Jennifer are "cautious", but if you check the husband and he is preoccupied, in that case, you and Jennifer become "carefree". While carefree, your sex meter climbs faster (1.5 multiplier?) and also some scenes may have a carefree variant.
I hope you find some of this useful!
I really like this game so far and I think it will be really fun and sexy!