The last Soul Exchange of 2022 gave everyone Ludwig for 15 souls. This hero is perfect for events because he charges up the adjacent heroes’ mana over 6 turns…pair Ludwig with a hard hitter like Khufu and it makes these events quite easy…
[Soul Exchange is probably the single most important thing in this game. It lets you trade dupe 5* heroes for a hero of your choosing as offered at the time. It occurs every 3 months. I did not realise this when I first came back…wish I had known after coming back cold, like you. Second most important thing is probably the Fated Summon. Fated Summon = 100 dud pulls and no 5* = 1 free hero of your choosing per the list at the time. The heroes are slightly outdated in FS, but there are some gems to be had there]
Then there are overhealers which boost health beyond maximums. Without these, it is almost impossible to beat impossible in the towers (I would say).
The Soul Exchange that just went by a few days ago offered Arco, an overhealer who also gives beefy minions. There are a few 4* overhealers here and there that are important: like C2-Kiril, and there’s a blue one from Challenge Festival II which I can’t remember the name of, a yellow 4* in the War of Three Kingdoms, Costume Gaideirus…I think it’s pretty important to snag at least a few of these for events
The best you can hope for is to accumulate as many 5* dupes as you can, and wait for the right heroes to come up that meet your need.
Hope I have answered this particular part of your question.
Check out these threads if you haven’t already: [Master] -- 👻 Soul Exchange
Now in terms of the current meta, this is a completely different question - and has already been answered by people above.
I think the heroes you need to farm coins and finish events, can potentially be very very very different to the heroes you need for war and raids at the top level…
Lol we both belong to this generation…