Well, what can I say...
Here you can combine double-shooting archers and powerful units (druids and trolls), don't forget about centaurs.

Titans > liches > trolls > archmages > druids > elves > archers > halflings > orcs > centaurs
I think this is true, especially regarding liches, trolls, and mages... it all depends on the situation.

Trolls were one of the most powerful ranged units - they could also regenerate. Of course, they can't be compared to titans, but I would give them second place. Centaurs are inconvenient as ranged units - they are large, too difficult to cover, and without cover, they die very quickly. Liches are simply amazing. The rest are approximately at the same level for me (not in terms of strength, but in terms of personal assessment).

I'm a little confused by the 25 hit points of liches. Yes, they have excellent defense - 12, they deal good damage (8-10), attack 7 (sometimes worse), speed is above average (5), however, 25 health combined with a price of 750 somehow...
Just one lightning bolt with a magic power of 6 destroys six liches, which is 4,500 gold!!!
What do you think about mages and trolls (remember, we are talking specifically about non-upgraded ranged units of level 5)?

I would like to hear an opinion, is it possible to create an army consisting only of ranged units? After all, titans have no penalty in melee combat, so they can also act as melee units. And trolls have regeneration. But, apparently, only barbarians and wizards can create such an army.

Ranged units are powerful, but how do you properly protect them from units that fly across the entire map at once?

Well, those who fly across the entire map usually move before ranged units :confused:

This is generally the weakest point of all ranged units - speed. Even titans are quite slow compared to other high-level units. So, there is always a way to block ranged units. However, this does not work with titans.