First and foremost, I have very much enjoyed SCP THE TABLETOP RPG. The book itself is well written with, in my opinion, similar vibes to Cyberpunk 2020 in several respects (ie similar messaging on player-GM relationships but with less snark), which I consider a good thing.
What I normally look for in a TTRPG system is FAST character creation, dynamic combat being encouraged mechanically, and enough mechanical specificity to account for a wide range of shenanigans while not being dense to the point of simulation. I believe this game performs excellently on these fronts.
Character creation in SCP THE TTRPG is a unique version of a point-buy system; instead of having a pool of fixed, concrete numbers to distribute amongst the character's stats, there is a pool of dice (D8s and D10s) that are assigned to each primary attribute. The more traditional point-buying comes for the skills: for each "Knowledge", "Skill", or "Ability" a number of points may be assigned which are directly added to any appropriate skill check. You then select an "Appearence", "Body Type", and "Reasoning" (ie superstition level), each of which affects a handful of stats, and finally fill in the remaining substats based on the previous numbers. At first, charcter creation seems somewhat intense, but there are notes on the character sheet which help the player keep track of how to determine substats like HP and Movement Speed. After making one or two characters, the process makes a ton of sense and can be done very quickly! When it comes to equipment, there isn't much streamlining that can be done when it comes to physically writing down item stats, but there are "Loadouts" which the players can purchase with any starting money provided by the GM, which can set them up with all the equipment they need for a given role, meaning no need to comb through item lists figuring out to get.
Combat hits just the right balance of crunch and simplicity for me. There are 8 general types of actions you can take (attack, move, use item/reload, grapple, analyze [basically permanently boost initiative mid-combat], defend, reaction, and aim), some of which can be broken down more for specific rules (ie Melee v. Projectile attacks). While there may be a moderate number of rules to keep track of, they are very straightforward, and players are rewarded for thinking on their feet. For example, using the analyze action, a player could hit #1 in initiative order, which grants various bonuses during combat. Another might decide to move behind cover and take aim, so on the next turn they will be harder to hit (cover improves defense scores) and will have an easier time hitting an enemy (aiming increases to-hit). In addition to normal damage, it is possible for characters to trade a received critical hit for mutilations with various temporary or permanent effects that hamper their effectiveness. Decisions such as "Do I take cover and aim for accurate attacks or just spray from the hip for immediate attacks" and "Do I suffer critical damage or get a potentially permanent debuff" make for a more engaging system than the "stand in one spot and spam attacks" that certain games can fall into. One final note is that the combat is fairly lethal, with lots of dice being rolled per attack and big damage numbers. It's something I like, but may not be for everyone.
Interacting with the gameworld is not terribly complicated. There are a total of 65 skills governed by 8 overarching primary attributes that can be used to perform the various tasks of TTRPGs. Skills span from Cooking and Caretaking to Religion and Psychology, Stealth and Lockpicking to Demolitions and Driving, and everything in between. Beyond the skills, combat, and SCP-specific rules, there are few rules pertaining to interacting with the environment. Due to the fairly exhaustive nature of the skills and a few relevant items from the combat rules, a GM can determine fairly easily how to rule in a given scenario without needing to memorize or reference a large number of extra rules. Additionally, the rulebook is divided into various sections denoted by a "Security Level", which segment the book based on comlexity of rules (ie Level 0 is just the basic rules needed to play, then Level 1 adds extra rules for firearms; Level 2 explores rules regarding creating in game squads and the associated mechanics, and by Level 5 you have hit the GM info). There were even several instances where certain bits of rules are marked as [REDACTED] in earlier sections, and in later sections those portions are unredacted, with expansions on the associated rule. This can greatly help prevent new players and GMs from being overwhelmed and each section expands nicely upon the last.
TL;DR The SCP TTRPG is a system that is only moderate comlicated at worst and has a lot of really fun ideas and mechanics when it comes to character creation and combat.