Marking a starter is usually always recommended. A starter will ensure you starting with healthy active yeast. On the packet of yeast is a best used by date. The closer you get to that date the less viable the yeast will become. I always recommend using a starter.
Now you are correct in your understanding that yeast will create esters during the reproductive cycle and therefore the more reproduction the more esters. Mr. Malty has a great article on yeast starters. It’s an excellent starting point.
Fourteen Essential Questions About Yeast Starters
Based on my experience with Belgians I would recommend pitching a pack into a two liter starter at about 1.040 gravity. May people feel that your starter’s gravity should match your wort’s gravity but my opinion is that a 1.040 gravity wort works just fine. 3 years of starters with wort gravities ranging from 1.035 to 1.085 and I’ve seen no difference. Even with a 2 liter starter you’ll still get enough growth to achieve the profile you’re looking for. 1388 is described as a robust flavor…..under pitching may push the flavor profile overboard but I’ve no experience with this particular yeast so perhaps someone else could chime in on that.
72-74 is a bit high of a fermentation temp for a non Beiglain beer. The temp range on the 1388 is 64-80f. Now that’s an optimal range and may not produce the best beer at either extreme. But 72-74 seems to be right about the middle so I would have to say that it should be ok. My recommendation would be to chill it down to the mid 60s, pitch the yeast and try to keep it in the 60s for the first 24 hours. Then let it rise to the low to mid 70s. Keeping it cooler the first few days will inhibit the production of the “hot” alcohol flavor. I say go for it, no time like the present.
I fermented a Wit very hot, high 70’s, and it’s horrible then fermented a Saison as described above letting it rise into the 80s and it’s come along famously.
A lot of people poo-poo the Jamil Show but it helped me out a lot when I got back into brewing a few years ago. Look up the Belgian Strong show, it has some great advice.
Belgian beers can be a bit tricky, good luck.