As I stated, if there is "no other way" to handle the crowd, par/pre-cooked pasta MAY be the only way to go. TBS, I don't condone par/pre-cooked pasta for operations under MY control. Can it be acceptable? Possibly, depending on the chef's desires.
Sauces that require more cooking than "a la minute" are, generally, all candidates for being held under refrigeration for last minute heating for service, among others, marinara, bolognese, or other "slow cooked sauces. Probably some cheese sauces as well, though that might prove "tricky" with extended hold times. When my restaurant was open, I ALWAYS had marinara and bolognese in the refrigerator next to the range top.
Some sauces, like Alfredo (a la BDL), are worth waiting for and, personally, I would not even attempt to "hold"!
Now, the above is colored by MY personal viewpoint and how I would serve in MY establishment. I do not do "fast food" but I do "good food fast"!
The "key" question, IMHO, is what YOU find acceptable for YOUR guests and establishment. If par-cooked pasta and "hot held sauces" are acceptable to you, go for it. You may have to "experiment" to find the best techniques to work for you.
IIRC, I remember seeing a "culinary instructor" cook pasta al dente, portion it, using a long tined fork, and placing on a plastic lined sheet pan, covering it with plastic and a damp towel, and holding in a warm oven. No water bath to heat and wash the starch off; either plate and top with sauce or toss with the heated or a la minute sauce, as desired. That particular instructor also advocated no oil in the cooking water and draining the pasta in a "restricted flow colander" adding oil to the cooking water at the time of draining so the oil would "seep through" the pasta, coating every strand, FWIW.
Now, remember, I am OLD, Opinionated, and Crotchety!