Rather than using a solid stopper, which might blow out once the CO2 produced by the fermentation gets going, I would suggest a silicone stopper that burps as CO2 is produced.
As to the pressure dynamics, I really don't know, but I try to get the wort below pitching temperature before pitching (and imposing an airlock or blowoff tube) and this allow for a slight rise in temperature from that point, so I have not experienced the dreaded "suck back" at least not to levels that are noticeable to me.