Should a splash page linking to other multisite instances also be a multisite instance or a bare HTML page? This is the situation:


Global domain: www.domain.com (exists of one page, with links to other 3 subdomains)
Sub domain 1: sub1.domain.com (full website)
Sub domain 2: sub2.domain.com (full website)
Sub domain 3: sub3.domain.com (full website)


My question:

Is it overkill to also create a site for the global domain? It will only have one page (frontpage). Or what is the best practice to accomplish this? The global domain is just a landingpage where you can make a choice between the 3 subsites.
If you need more flexibility on the long run, you better create a separate website for the global domain. Keep in mind that it will require extra resources on your server.

If your global landing page is simple you can consider the option to only use a HTML page. Keep in mind that this will give you less options on the long run.