I too have to chime in with my dislike of sandboxes. It seems all well and good to add "different" content depending on the time and place, but that's actually just a waste of time. All that content can be put into the storyline and continue going, and all sandboxing really adds is a time waste grind, even if the grind is seeing a certain sexual situation, that is what a replay gallery is for. Every sandbox I have tried seems to miss out on several key elements of life, so it might as well not bother. A for instance is a non-sexual date that lasts for dinner, that's going to be over in at most a couple hours, and that couple hours takes a whole "evening" which is just silly. I don't know about anyone else, but in an evening, I am able to read a few chapters of a novel, play a game, feed my cat, have a shower, and do some chores around the house, and that is on a slow day. The other trope that they tend to get bogged down by, is that a guy in sexual encounter at a youngish age of 19-25 going once, then being dead for the whole "afternoon" section, yeah at that age males are at their sexual peak and tend to keep going for hours, and sandboxing one scene is a waste of time for that. Those time/place constraints are actually worse on a story than to just tell it and add all the content in.
On a technical note, sandbox games means clicking a mouse repeatedly, and I don't know about others, but I try to use my keyboard more than my mouse because damage to my hands. All that clicking wears out my rather expensive mouse (50 USD) for not enough content. I go to VN's for a good story, and sandboxes lose story for time wasted.