I would suggest to migrate this question to OnStartups, but when choosing "Off Topic", only "meta" appears as a migration suggestion option.
Can we have additional SE sites added to the list, OnStartup being the main migration target?
The most frequent destination for questions migrated from the site is actually Bitcoin SE (a total of 3) where 66% were rejected. OnStartups has received only one question from Personal Finance SE which (seems to have been) accepted. The second most frequent inbound route to Personal Finance SE is actually Travel SE, a total of two, both accepted.
At this point, it's probably worth asking where you think inbound migrations would make sense as well. The heaviest comes from Quantitative Finance SE, a total of 6, where you've only rejected 16%. OnStartups hasn't sent any questions here to date.
The site just doesn't see a lot of migration activity, and that's good, but it makes establishing the initial routes a little difficult. OnStartups probably isn't going to be in your migration path - at least initially. There's really not much data to support adding any beyond meta, we'll keep a close eye on it once you get your design and your graduation status is completely official and add them as migration data (by mods) suggests sane paths.
Migration paths for sites besides meta won't exist until the site leaves beta, according to this answer. Based on the migration stats, it does look like a fair amount of questions have been migrated there over the last few years (although not as many recently). I don't know if enough questions have been migrated to warrant a separate migration path. I don't know what criteria are used to decide that.
That being said, if there is room for five sites (including meta.money.SE) in the list of migration paths once the site leaves beta, there's probably space for onstartups too. It certainly looks like it's in the top five sites that receive migrated questions.