I waited for the next 1/2 AP Campaign to do my remaining Interludes (which amounted to 40 or so). Was pretty time consuming, but I finally caught up with everything possibly doable. Three are still missing because Ascension requirement not met.
Same goes for RUQs. Even more so, since pretty much all of them have 5 ticks to clear at a cost of about 20-21 each.
But more importantly, I can’t do any of them anyway, because I have hardly any low-star Servants fully raised. Might happen after GilFest, but that has yet to show.
I’m doing the new ones (like Melt, Kiara, …) that came out around beginning of the year(?) right away. I’m using all of my Gold Servants rather frequently, so I’m definitely not waiting for anything to strengthen them.