This sounds like a fabulous plan with no possible downsides, risks, or sharp edges.
The risks are a lot smaller than you think they are, because of new reactor design. Nearly all of the nuclear reactors in the world are still using a design that's 70 years old, that requires active cooling and doesn't fail safely. We have much better designs now, at least on paper, designs that simply can't melt down, whose failure mode is to simply stop. But no one builds these new designs on industrial scale because they're unproven, and there hasn't been much funding for doing all of the engineering and research needed to develop them into fully-functioning designs that can be.
I'm skeptical that small reactors are really the best way to actually deploy nuclear power on a large scale, because of security concerns, but starting small is the best way to validate and refine new designs. And modularity is clearly a good strategy for making deployments of varying sizes cost-effective. If you can develop a cost-effective module that can be manufactured in large numbers, you can build large plants by clustering them.
The new designs shouldn't actually need much operational oversight -- if something goes operationally wrong, they just stop functioning -- but they'll still have highly radioactive cores which, if extracted, could be pretty terrible weapons. Not to make nuclear bombs, but to greatly enhance the damage done by conventional explosives, by adding radiation hazards that linger for years. So, security will remain an important consideration, and the SMRs should only be deployed where security can be assured, which will in practice mean that most are deployed in large clusters.
This all assumes that the safety, effectiveness and cost-effectiveness of the new designs proves out, of course. The only way to find out whether that will be the case is to try.
