Before I get started with my [hopefully not too long] paragraph on this, just know that my opinions are just that...my opinions as someone who's played TTT for far more than a sane person should.
Generally, even if you get KOSed by the Detective early on (at least for me), it's never been a really big deal. People forget about Detective KOSes quickly, or you're able to play strategically and pick off people without being spotted, or just go crazy and run in and spray everyone down, part of what you're supposed to do as a T. On maps like closequarters, yeah, it's sometimes annoying, but not as often as you'd think (once again, at least for me). Maybe 1 in 15 T rounds on a CQC map will a Detective KOS actually end my T round, when I get Detective KOSed in nearly all of them.
As for Detective's "buffs", 125 health and armor doesn't make much of a difference, considering how they're a high value target with the ability to DNA scan bodies as well as give a lot of credits to the T that killed them.
All in all, the buffs don't actually buff the D too much and is easily outweighed by the fact that they're targeted and a competent T knows how to deal with the armor (a.k.a. spray them down), DNA Scanner doesn't make the game that unbalanced since logic is already heavily restricted on our servers, and Detective KOSes are the one sure thing that people can use, Innos also constantly forget about Detective KOSes anyway, or some Ds don't actually call it which makes it useless, I pretty much agree with everything
4g0tt3nSou1
said above. TTT works well as is, and is balanced enough -- mostly due to (this is not meant to be rude, and also forgive my bluntness but) the general incompetency or carelessness of a TTT Inno.
Now, in response to some of your points:
Another thing is to make regular admins be able to /beacon people. Not sure why it's manager only when half the server delays and we have to sit and wait 10 years.
That would be useful yes, but is it worth bothering with having to re-do part of the MAUL plugin? Not really, current strategy of watching the Ts & Innos, seeing if they're doing anything, and not so kindly asking them to start pursuing the round works well enough. If they're running in circles, it gets annoying at times but it doesn't happen all too often to warrant the need for tech and LE to bother with this.
I don't think you understand fully, detectives can buy a DNA scanner at the very start of the round and ID the first body they see and instantly can call KOS. To me, personally, that just ruins the fun. When there are 2-4 detectives it's very unlikely that there isn't a KOS on you before mid-round if you're getting ANY amount of kills.
See above point on Detective KOSes' uses
DNA scanner should be at least 1250 just so you cant buy it off spawn, you dont even need to be competent, just buy dna scanner off spawn rush the first body u see and use the "kos last scanned" bind
Sure, but once again, it doesn't do too much since people forget about Detective KOSes, Ts can play properly and not get caught, pick people off one by one, go out guns blazing, and a million other things
if u have a competent Detective they will easily kos 3+ traitors in the first 30 or so seconds of the round
See above
It'll have to be a
-1 from me on the Detective debuff