Coax Ethernet : terminate or necessary only splitter?

I've just learned about moac. Some of our upstairs bedrooms have very poor wifi reception. I'm torn on how big a splitter to get. The existing splitter is an 8 way and not fast enough.

I don't know how to explain my situation without getting long winded but let's say I have primary use for two ports, occasional use of one/two more, at max five if I want to invest in additional endpoints (but two will mostly be unused. Think college kids coming home).

We're looking at 2.5g speed. Cable modem (Xfinity X8) is in my office. I absolutely need three endpoints. No cable TV currently.

My question is, is there that big of a difference if I cap the occasional use ports of a six way vs getting three or four way for the most common scenario? Or is the loss so minimal it's not a big deal. The splitters are the same cost.

I get really anal about stuff like this. :)