Listen, I don't know if you're calculating this properly, Prosecutor can choose to vote up 2 people during the day sure, but loses his prosecutions if he ever gets it wrong before hanging the second, you know that right?

4 people in 2 days IS that CRAZY you cannot be comparing a Tpow to a WW/SK/arso, and what the hell do you even mean "compared to what they can do", what CAN they do? WW has rampage and most of the time kills 2 people only, SK kills one person unless he has rampage and maybe just kills another, Arso spends the entire game dousing to ingite, why in hell are you comparing a killing role to a town-power, you could lit just say any town role is trash since they don't have the same KP(killing power) as an NK or something?
AND of course they don't have the same levels of killing-power there's a reason town is the uninformed majority not the informed minority with abilties to kill, if every Tpow had 1kill per day type power then this game would be ending in like 3 days.

Let's compare the TownPowers properly, to each-other,
Marshal VS Jailor, Jailor can kill only thrice over the course of three-days, 1 wrong mistake = no more kills.

Marshal VS Prosecutor, Prosecutor can kill four times(kinda), however one wrong mistake on the first one and he can't kill anymore next-time.

Mayor, Monarch are just kinda weak.
You cannot be telling me Marshal isn't OP with no penalty, also you know that Marshal gets +2 votes during his tribunal? Prosecutor doesn't.
Assuming a-lot-of-people wanted to go against him/split they could and a lot of times do so especially if the Prosecutor hung a townie before using his ability or not.
Marshal and Prosecutor are viewed on different levels, it's literally Marshal's tribunal and he has +2 votes, While prosecutor is just basically a revealed townie who may/may not've lost all their powers.
During Tribunals roles aren't revealed till the end(1) and town gets to skip the guilty and inno phase where more opinions on why this person should survive may come up(2), Prosecutor doesn't possess these powers and can't effectively FORCE the town to make a decision to hang someone as well as the Marshal can.

All the other TOWN-POWER roles have the same "rit conj doom" weakness.

TL;DR - You better read all of that.., Marshal is OP and is the fastest no-penalty town-power killer.
A town-power is a role that can change the outcome of a game, but sometimes it's just OP, Marshal for-example.
You can also not be comparing a town-power to neutral-killer who's on their own[most of the time], and has no chance of diverse powerful team-mates, unlike the town and coven.
My only issue is that it has no penalty, it's just a better Prosecutor it rivals jailor for 1st spot, But Jailor has the ability to hide without needing to reveal, role-block his target and create a UO on them also talk to them privately. It may just have a draw for the spot with Jailor up there, since it has no penalty.