So the static gameplay is half due to the bots, and half due to the current game mode and map design. The premium spam is mostly due to the bots. Most humans actually move around instead of island camping, since they care about winning and know they’ll lose if they don’t contest the cap points.
USA and USSR 4.7~6.0 would be the most competitive, fun, and lucrative, if not for the constant uptiers and static gameplay from all the botting. Currently I find 4.3 destroyers and coastals to be the most competitive and fun, if somewhat less lucrative than higher tiers. You don’t see any 5.7~6.3 cruisers which are popular with bots, and you can actually get quite a few full downtiers(where the only bots are Gaijin official bots). 5.3 cruisers are a rare sight. Most of the time the worst you can see will be 4.7~5.0 destroyers(mostly using bots) and cruisers which you can deal with, with some skill and luck.
Coastal in general is also competitive and dynamic and fun, but the BR compression is even more insane than bluewaters, and most small gun-only boats can’t do anything against frigates and destroyers. The queue times for lower BR coastal can be quite excessive as well.
I’d say the Italian bluewater tree is the hardest, as their only decent ships are at rank 4, with ranks 1~3 being the absolute worst and rank 5 only being ahead of France(which is grossly incomplete). But Italy is hard in a frustrating way, and not in a challenging and fun way, so if the latter is what you want, don’t try Italy. The Japanese tree(up until about rank 4) is about the only one that requires mastering a particular playstyle, that of using torpedoes as your main weapon instead of guns. IMHO that is also mostly frustrating and not challenging and fun.
But what I really think you should aim for is getting some good 5.7+ ships and playing naval EC(Enduring Confrontation) with them. It’s a great multi-hour experience on huge maps with various different objectives. It’s much more dynamic and quite different from the ‘normal’ maps and game modes. Not having any bots about, and having many human players actually working together is also a plus. Queue times can stretch as long as an hour though(usually much shorter than that but still very long compared to normal matches), and the servers can be unstable at times. And the rewards(both RP and SL) are less than normal matches on a per unit of time basis.
Naval EC is available every week from Thursday 11:00 UTC to Monday 11:00 UTC. It rotates between AB(which is actually pseudo RB with torp/bomb/rocket/etc reloads, AB torp warning distances, enemy vehicle names on scoreboard, and using AB BRs and reward modifiers) and RB difficulty every 24hrs. So it’s pseudo RB from Thursday 11:00 UTC to Friday 11:00 UTC and from Saturday 11:00 UTC to Sunday 11:00 UTC, and true RB from Friday 11:00 UTC to Saturday 11:00 UTC and from Sunday 11:00 UTC to Monday 11:00 UTC. Make sure to read the mode description in the even tab, as there are some requirements and restrictions.
Hope this helps!