I’ll ask my rosh kolel how to understand the mishna berura.
Damoshe, there is nowhere that says to only to the mitzva through wine only. If someone prefers, he can have a drop of wine and the rest from other drinks or even skip wine altogether. I personally get nauseous sometimes from wine, but I have an easy time with whiskey. Also, there is a mitzva to eat and drink the entire day, not just after hamotzi. I usually start drinking after mincha gedola. Regarding bentching, you can keep some control of yourself and still be able to bentch. Alternatively, you can bentch in middle of the seuda after a few courses and still continue with the mishta. For maariv, there are many later minyanim depending where you are. Also, you don’t have to be completely back to full strength in order to daven so long as you’re sobered up enough to act and talk regular (as opposed to completely sober in order to drive).