What are the practical issues you're concerned about? Dev time? performance / reliability?
So dev time, well the last THIRTY YEARS of dev time haven't gotten me any anything I didn't have already.
For example, what if you want to use your spreadsheet when you're not home? Never happened to you? Well, it happened to others.
Or to use my previous analogy, you're essentially saying that because you can build your own custom designed car from parts, pre-built cars are useless.