The top gun on the tiger 1 is not unhistorically powerful. In fact it's probably a bit underpowered in WoT actually if we disregard the fast reload..
What's unhistorical is that the gun is mounted in a Tiger 1 at all because it literally wouldn't fit in the turret.
However imho the tiger1 is one of the best heavies at its tier because of its gun that manages to be a threat to tier 8 heavies and with careful aiming even some tier 9's.
Also no don't even think about relying on the Tiger2's armor unless you hide the lower glacis AND your opponent is tier 7. Tier 8 heavy tanks can just put shells through the turret front and those without the needed pen can just perforate the lower glacis.
I played a few with the loltractor and the russian one, they're all right. Then I started on the T1 which is pretty fun, that 5 shot cannon can tear stuff to shreds, then scoot away while reloading.
I might play the german line first as I've always been a panzer fanboy, though the British Tanks are pretty interesting.
Honest suggestion. Get the KV-1 and learn to angle its armor.
It's pretty literally the best tank at tier 5 for money grinding.
The armor is great. The guns are very good and the speed is acceptable.
Also an AT-2 might be a fun idea if you want to get a taste of playing something with hilarious amounts of armor.
To put things into context... some tier 5 tanks have issues penetrating its side armor and it's basically untouchable to tier 4 tanks unless they get to fire at it's thin rear armor.
And it's only weakspot is the 100 mm thick rounded coupola (the KV-1 for comparison has 75 mm thick hull armor all around and it's top turret has 110 mm all around) you have to hit dead on or your shell will bounce off and many tier 4-5 tanks have around 110 penetration on their guns so even a square hit can just get a low penetration roll and get bounced.
A really hilarious machine overall when you get to play it as top tier.