My turnkey spinoff program is based upon your taking an IBC public. Your insiders should hold their shares in your public IBC through separate IBCs that they form. The insiders won't get their Golden Parachute for several years. It will take you that long to build your company to be a suitable acquisition candidate for a giant in your industry. If your insiders hold their shares through an IBC, they will have more options at the time of the sale of your company.
More options are better than fewer when it comes to dividing hundreds of millions of dollars.
Using one or many IBC insiders isn't important now. It may create a nasty fight in five to seven years. If you aren't certain about the impact of money on your partners, divide the pot before there's money on the table. Create separate IBCs as your public IBC company insiders. If money is secondary to the satisfaction of making your company a success, then a single IBC insider will work for you.