It makes good on the potential and promise of UC4's improvements over past games. There were multiple instances that felt like direct responses to things I found disappointing in 4.
If you almost really enjoyed 4 because of the incredible battle arena designs and story, but the constant start-and-(come to a complete, screeching)-stop pacing held it back from being engaging, and if it felt like the newer stuff like sliding/rope swinging/open areas/etc. seemed cool but underutilised as if the "loop" part of "gameplay loop" was never properly closed with those aspects, then Lost Legacy is for you.
The open areas in 4 were woefully empty despite being gorgeous, and there were only a few scant environmental puzzles that made it feel worthwhile—one of the most interesting environmental puzzle (the well/Jeep/wooden beam thing in Madagascar) was for a rewards that had no use from a gameplay perspective (treasure collectible), and only had some diary entry that felt insubstantial, even from a lore perspective. The conversations between Nate and his brother were occasionally insightful, but the vast majority were just them qupping back and forth (that does get subverted in a really good way halfway through, but the game drags in a lot of places which in turn makes that note typical conversing seem rote).
Compare that to Lost Legacy where you hidden special weapons (with a decent amount of ammo!) are all over at enemy encampments, each conversation between the two leads gives meaningful insight into their motivations, and the spatial puzzles are better and make good use of climbing in interesting ways. The lack of crate pushing was welcome too, and every section of traversal feels distinct as opposed to 4's overly long, samey cliff faces (which feel like a remnant from when the game was going to have a stamina meter).
if you hated 4 through and through, maybe skip TLL, but if 4 just sorta missed the mark, give it a try.
