Some of my favorite visual novels include complex gameplay. At the same time, there are VNs which I didn't enjoy due to obtuse gameplay mechanics, frustrating difficulty, or both.
Everything that Katlyn8638 mentioned is an indie VN for Windows and other computers. Please state if you're willing to consider visual novels for consoles or mobile devices. Also, mention how much you're willing to spend. If I remember correctly, Hanako Games' products usually cost $20 US each.
A full fan translation patch is available for the Windows version of Utawarerumono. If you're looking for a strategy RPG and you don't mind adult content, consider it. I took a few minutes to look for game specific reviews. Teira's Space enjoyed it, as did KorganoS. Finally, if you're willing to import it, read the relevant guide on r/visualnovels. I searched amazon.com for "utawarerumono," filtered results by category: video games, and selected to show adult items.
In the recent past, JAST USA has localized some VNs with gameplay. The latest is Girlish Grimoire Littlewitch Romanesque, which is a raising simulation. No importing or patching necessary. The current translated versions are paid download and a DRM-free game disc. The company is also using Steam Greenlight to get a censored version available for sale there. As for reviews... Twinfinite enjoyed it. Eroge Bus has a review available as streaming audio or MP3.
Heartache 101 is freeware, and since it was made with an RPG Maker program, it might only work on Windows. If you're looking for plot or complex characters, look elsewhere. This is a simulation game inspired by a number of untranslated '90s titles. I played it for several hours, and enjoyed it more than some commercial games. It has an opening story sequence that can be completely skipped. At first, there are just a few options. The game world slowly expands by increasing stats and trying different things.
None of the five Princess Maker games have full, official English localizations. PM2 was the closest -- it had an English beta which is considered abandonware. That said, there's some notable games inspired by the franchise. I played Spirited Heart a while back, and mostly enjoyed it. It's an indie product and a challenging simulation game. The player controls the girl rather than her guardian, and after a prologue, she is already an adult. The Steam edition includes all possible romantic pairings, while Winter Wolves lets the customer choose. For another perspective, consider the freeware game Prince Maker - Braveness. The player raises a boy, and according to the fan group that translated it, there's a story as well as a complex simulation.