I put about 45 minutes of time into the game before rating it, and I have some seriously mixed feelings.
On the one hand, there's a fair amount of cleverness here, and who doesn't like an adventure through time? Meeting famous people, reading clues off the Mona Lisa. There seems to be a fair amount of depth--a lot of conversational topics, a lot of description, and those things are always good.
There's also some reinventing the wheel. Implementing a parser game from scratch in, what was it, QBASIC? It's ambitious and impressive, but the result is something much like an existing parser like Inform, only without some of the familiar shortcuts built in. Things like having "unlock door" just use the key you're carrying, if it fits, rather than making you specify "yes, with the stupid brass key, what else would I use"; or avoiding a little bit of guess-the-verb (I went through several variations on "FLIP SWITCH" before I discovered I needed to push it, which isn't a thing I usually do to switches). Or, for that matter, taking things that are visible even if they're in/on other things, without the need for TAKE ALL FROM IT.
There also feels like a whole lot of traipsing back and forth: I checked the hints while in the cave in Timeline 3, and discovered that I needed a thing from the cellar that I'd gotten the means to acquire but hadn't gone back to do yet, which meant: out, up, n, n, n, n, s, e, d, do the thing to get the thing, u, w, n, fiddle with the bracelet, s, s, s, s, d, w...it amounted to a whole lot of walking back and forth from place to place.
Some of that traipsing was really unintuitive, too: I looked in the Canteen, made note of a few things, kept going south, found the rest room, and then...the hints told me that now I needed to go to the Canteen to trigger the next event. (And, later, the hints told me that I also should have gone back to the restroom, which didn't particularly seem like a thing I needed to do.)
At this point I'll admit to being a little frustrated, so when I realized that I didn't actually know what my next destination was--did I miss a comment from the bowler, which I couldn't go back and retrieve? Had someone dropped a thing on the floor that I hadn't picked up, or handed me something the game didn't identify so that I had to look at my inventory and see what looked unfamiliar?--I decided it was time to set it down. I may come back to it; we'll see.
As a last thought: visiting da Vinci was fun. Visiting the Texas Book Depository, and getting the weird rewrite of history there, but just having to stand around and wait for the gunshots...that was less fun. It felt kind of distressing and flippant, to be honest. Not enough to make me stop playing, but enough to drain some of the fun I was having.