So many western VN seem to fall into the trap of wanting to do tons of branches and paths and a bunch of LI which leads to each update taking longer and longer and feeling shorter and shorter even if there is still a lot of unique content if you follow every path, but the whole thing feels unsatisfying for everyone. Having both Ian and Lena to follow already creates a lot of branching by itself, but giving them so many options and different types of relationships to have with each other and with others creates a mountain of work that you can't possibly do in any reasonable timeframe. You end up spending years waiting for the story to advance much and could spend literally 1 or 2 maybe even 3 entire years waiting for meaningful content with your chosen LI. Authors really need to reign in the scope. Evakiss tried to make so many people happy, but I think more and more it leaves no one happy.
While i easily prefer their art-style , and overall the Japanese culture , and Anime subculture ... i just feel that most Japanese erotic VN are just worse . Their update schedule is likely shorter , release pace quicker , but it's not necessarily a matter of western games having too many choices and options . You can pick a few Japanese VN requiring built in timecharts , to keep track of choices and events . However they are drowning you instead in repetitive walls of text , while hiding that they have very few adult content , and some even got very little scene variations . And then the bulk of the regular JP VN are incredibly short . Some western VN you could skip the whole game and unlock the gallery , and still find stuff to enjoy ... (even if i find the idea ludicrous) . It's not rare to have a tiny gallery of pics and animated scenes , if you try the same in a Japanese VN . Some had barely one page worth .
Anyway the point is , it would be weird if , they took as long to develop , as they are usually shorter games with little content . And it would expose recycling experts like Atelier Sakura . I don't think the western VN genre need to take cues from them , outside of using occasionally their artstyle and themes . You can basically find the equivalent of a lot of JP VN , pace and content wise , in titles from western studios like Neverluckystudios (couple , a knight tales , triangle) , or short repetitive adventures from the likes of Dumb Koala Games