It would definitely improve upon it, but youd run into a few issues still.
1. Would you start where you were bred, or back at the start?
2. Would you keep plot items (eg keys to unlock areas), and would you have to refight bosses you previously "killed"?
3. How do you deal with multiple generations of breeding in terms of both gameplay and visually?
4. Roguelikes generally use randomized rooms with the same bosses, how would that be explained in game?
1. The bosses are going to be the strongest enemies, so obviously youre going to want to breed with them. That means that you will still have to do runs where you intentionally lose to each enemy, then restart, then intentionally lose to the first boss, then restart, then intentionally lose to subsequent enemies, then restart, beat the boss again (with an inferior breeding bonus), then lose again, restart, etc. That is still going to be grindy unless you really move away from standard roguelike mechanics. If you start straight where you died it solves some of it, but again its less of a rogue like as the stakes dont really exist.
2. If you have to start from scratch you have grind, if you don't you have to explain what happens while youre growing up and why you still have all your stuff/why no one has replaced the bosses, also the stakes are lowered.
3. Multiple generations of monster features would be very hard to do, youd probs be stuck doing a text based game - and even then itd take some doing. Gameplay wise, do bonuses stack? Maybe you could have the bonuses get weaker each generation and limit it to three generations of bonuses. So like, you die and breed with a bull monster and it gives you +9 strength, you die again and you breed with a snake and you get +9 agility, but now you only have +6 strength, then you die again and breed with a psychic creature and get +9 wisdom, and keep +6 agi, and +3 strength and so on. That could limit it, but itd still be hard to implement.
4. If the rooms are the same then starting from the start makes little sense, but if they are different then having the same bosses makes little sense because youve been moved somewhere new while growing up.
I have DEFINITELY overthought this, but there you go lol.