I was originally going to write an entire rant about the treatment Skip Woods gives to his female characters across both his outings in the Hitman franchise. I started going through Hitman (2007) with the intention of studying how Nika was portrayed as a character with the sole purpose of ranting about problems I saw in the way Woods handles women, female leads in particular (to be frank, there are few other female characters of note in either film; Diana is grandfathered in as an important character, but as I've ranted about before and will do so again, Katia's mother doesn't get the grace of a canonical name despite haunting most of H:A47). But, as I was doing that, I realized how similar the films are overall, at least in how they set themselves up.
One of the big points for me was the similarity between Katia and Nika, not in minute details but in overall character sketch: a woman in a bad position in life who is in need of rescue and (perhaps by necessity of genre convention) sexy. But not just any kind of sexy, she also has to be exotic. Nika is a Russian sex slave, a stereotype that may have flown in 2007 but needed necessary updating for 2015. So, Katia's mother is Sri Lankan Tamil. (She's initially implied to be mixed, which would slot her into the But Not Too Foreign trope where acceptable love interest territory lies, but when the story shifts gears to sibling team up mode and John is revealed to be a straight up antagonist, Katia is directly stated to be the product of mad science. It's highly probable that but for necessary modifications, she is a direct clone of her own mother--"You are the reflection of the woman I loved.")
There are other points I observed, too, mostly in setup (the details of deviation allow for the films to run different courses in their second halves). The prologue of the program that produced 47, the placements of any flashbacks (they taper out by the half-way point), the entire plot of "initial hit kick starting the action, followed by find the girl (whether that was an original goal or not), followed by kidnap the girl and deliver to her a series of key revelations, followed by drag her along to help on the mission". I don't watch enough movies (action movies in general or Woods' work in specific) to know whether this is scènes à faire or if H:A47 is really just Hitman (2007) with a different coat of paint. But I also don't think it's a bad thing. Lots of creatives have pet themes that make it into almost all their work.
The similarities also make it really easy to see where I think one version did better than the other. The prologue and flashbacks 47 has to getting tattooed from Hitman (2007) are something I prefer over H:A47, for example. Instead of the clinical sterility of medical exams, we get glimpses into the actual training the boys were given, including the implication that they were the ones responsible for shooting any of their number who tried to escape. 47 fixates on the tattoo because it caused him a lot of pain. There's a similar moment in H:A47 but instead 47 is asked if it hurt, and says yes. Coupled with the fact that in the 2015 version of the prologue, we do see 19 get his number, and the machine doing the stamping... gets it done in a couple of seconds and 19 doesn't even flinch. In the 2007 version somebody is using an actual tattoo gun, forcing him to keep a steady hand and 47 to hold as still as possible to not mess up the lines. To quote Dan Olsen: "inference is dramatically inferior to being shown."
(As a random aside, the monks in the 2007 version go completely unexplained. I think they were only included because in the second game 47 briefly converts to Catholicism and lives in a monastery. I have a web of theories about how the movies and games play off each other; this and 47's wearing the stripe tie from Blood Money for the first act are on that pin board.)
On the other end, I think Katia is an improvement, character wise, over Nika, and that boils down to one specific change. Katia is 47's little sister, a product of the same experiments that produced 47 himself. Because Katia also has Agent abilities, this handily allows her to participate freely in the action, in part because 47 spends the second half forcing/teaching Katia to use her abilities for combat until she can manage without prodding. Nika, for her part, acts in her storyline in spite of 47. She's told over and over again to stay put and not wander off or interfere, and she wanders off and interferes (though she does only interfere once; 47 scared her straight after that). Nika's primary story function is... teaching 47 to love? It's unclear, and her method half the time is to attempt to seduce him which, given his explicit rejection of the idea, counts as assault. Making Katia 47's sister eliminates the need for any weird "romance" dynamic involving 47 himself, and makes them much more equal in their interactions.
I want to make another point of comparison, too, and this is going to bring in ideas from the games. It's 47's relationship to his own name, which has clearly changed as time goes on. In Blood Money (which I'm certain influenced Hitman (2007)), 47 states "Names are for friends, so I don't need one." In Hitman (2007), he tells Nika "The place I was raised, they didn't give us names, they gave us numbers. Mine was 47." Both of these statements imply that he doesn't view 47 as a proper name but as something imposed on him (there's an argument to be made that in the 2007 film, the Organization used numbers as a means to strip their orphan charges of identity to keep them in line and foster loyalty).
However, in H:A47, he has this exchange:
Sanders: "So why don't we start with your name."
47: "47."
Sanders: "That's... not a name."
47: "No, but it is mine."
Additionally in the prologue sequence of Hitman (2016), he has this exchange:
47: "I believe they called me... 47."
Diana: "That's not a name."
47: "So make it one."
The acceptance of "47" as a name in its own right implies a version of the character more at peace with his clonehood and circumstances. In H:A47 especially, there are implications that the clones had a sort of subculture, or cultural identity among themselves (47 outright states that while each clone gets barcoded at birth, they only get the corresponding number stamped on them "when [they] become Agents", and if that's not a rite of passage I'm a wheel of cheese). One could surmise that their numerical identifiers were given appropriate significance, and I have nothing to go on here but I do think they lined up in numerical order for everything that required them to assemble in an orderly fashion (which is everything they could have been required to do at the lab).
The point I'm trying to make here is that as the Hitman franchise has progressed, the character of 47 has changed his relationship with the fact that his name is 47 (and everything that implies). Here I'm not going to say one or the other is bad, but I do think it's interesting and worth further study.