A few years ago, we were looking for somewhere to publish conference proceedings for a conference held at Surrey. We went for SciPost Proceedings, for a variety of reasons. Mainly it boiled down to the overall SciPost philosophy - that high-cost traditional journals do not justify their high-cost, and asking all our participants to pay an increased fee to publish the proceedings was not justified. SciPost follows on from the existence of things like the arXiv, which runs at low enough cost that scientists can deposit unrefereed preprints of their articles there for no charge to the scientists, and from where they can be downloaded at no-cost to the reader. SciPost adds, effectively, peer review to the system, and the uniformity and citeability of a journal style. Really the main addition - peer review - is something that the high-cost journals get the academic community to do for free anyway. With SciPost, at least the results of our free labour are free for all to see.
The SciPost family of journals started out with what is still the biggest one (in terms of articles published): SciPost Physics. It accepts papers in all areas of physics, and follows the classification scheme originated by the arXiv. So if your paper can be reasonably deposited in the physics part of the arXiv, then it can be legitimately submitted to SciPost Physics. So far, there are rather few papers in SciPost Physics that come from nuclear physics, particularly the sort of low-energy nuclear physics that I work on. BUT... I can announce that I have joined the Editorial College of SciPost and hope to encourage some nuclear physics articles to head there. If you are a nuclear physicist looking for somewhere to publish your next article, please let me try to persuade you to use SciPost Physics!