I just meant (by 'crumb') if you are getting a 'fine' texture result as opposed to more 'coarse' ones (larger), not how many dropped to the board when being cut. No large holes either? I presume that with all that fat, the resulting loaf must be quite tender and will store quite well. At any rate, I gather you are satisfied with that aspect of your bread so I have no really useful further comment there, other than to say that if you do have 'denseness' issues again, you may want to try adjusting the kneading time and/or rising times (upwards) if you can. That said though, that doesn't really address the yeast reduction problem, at least to any great extent, because I am not sure that machines are infinitely adjustable, even nowadays.
You may find, at least parts of, the following interesting reading if you have not found it already: KA article about bread machine bread making. That first KA article suggestion posted by keychris is also really useful and relevant here I think if your objective is still just to reduce the amount of yeast you have to use in each loaf so I hope you read that as well. The knowledge that you can reduce the amount of yeast in any given loaf by a substantial amount (perhaps down to as little as 1/8th of a teaspoon) is valuable. However, in order to do that, and also get more flavour as a side benefit, you will need to increase the rise time substantially. Is your particular bread machine capable of being set to let its contents sit overnight after the initial mix before going on with its job? If not, would you consider turning it off overnight perhaps or removing the contents to a bowl and then returning it in the morning? It would I think best also be done in a cooler environment (i.e. the fridge as others have suggested) but perhaps you can make this work on the counter if it is not extremely hot in your kitchen. I think this part is much more easily accomplished without using a machine at all frankly, but, perhaps you can figure out a way that works for you with the machine if you experiment a bit with 'timing' of the rises, etc. as opposed to just letting the machine automatically just go through its programmed cycles.
So that may be one way of attacking the problem you initially seemed to have. The other is, of course, to consider keeping a starter, either in the fridge or on the counter and once it is working well, perhaps reducing the amount of yeast required per loaf even more. Which direction do you feel is most feasible for you?
