My church uses home-made bread… just white wheat flour, whole wheat flour, and water. As you might expect, such a bread will be kind of tough or chewy. To avoid problems with crumbs, and with EM’s having to “tear” it into little pieces, it is pre-cut into little squares, except for one whole loaf that the priest uses (and the priest is the only one who breaks and distributes this).
The real problems I see are that (because there are no preservatives) the bread is sometimes a little stale by the time it’s consecrated. And if there is a lot left over, and it sits in the tabernacle for a few hours until the next mass, it gets VERY tough! So if the priest consecrates much more than is needed, there is a real problem (like if it’s more than the priest can consume himself). So we tend to put out only enough for the typical attendance, and if there are extra people then the priest can get some reserved wafer hosts from the tabernacle (at daily mass we use wafer hosts). Finally, it’s just not that easy to make a “substantial” bread from just wheat flour and water that is consistently edible - if you overcook it, or don’t knead it just right, it can be rock-hard.
You might ask why we bother… I’m not sure, except that the “substantial” bread has been getting closer and closer to being licit - it used to contain honey, eggs, baking powder, etc. There are enough people in the parish who like the idea of substantial bread, that the pastor hasn’t gotten rid of it, but has at least gotten rid of the inappropriate ingredients. And now that we find that a “licit” substantial bread is tough and chewy and not that pleasant, maybe people will be less resistant to switching to wafers.
Incidentally, does everyone check the ingredients on wafer hosts? I think some of the suppliers (but not all) include preservatives. Some wafer hosts last almost forever, and I don’t think that’s natural. Does adding 0.1% potassium benzoate make it invalid matter?