I'm a ToEE veteran of many many MANY playthroughs and I've gone through with every kind of character imaginable. In your example of a Giant rushing your party and the tactics applied - obviously the difficulty of the enemy will change, as will your party's power functional power level, entirely depending on the combat system in use. However, to bring up an example to counter your own example of archers wearing down a giant before he gets close - assuming you were using a party of 5 or more and at least 2 were archers, in ToEE you would have to score initiative (as per D&D rules) or enter battle yourself with haste cast or something, and have your archers ready against the giant either approaching or attacking - and a smarter route would also be to have a warrior with a reach weapon or with the enlarge spell ready for approach as well. This way you would have your fighter stop the giant and have your archers pelt him with arrows while your warrior then fights toe-to-toe (bad idea) or goes for a hit and run tactic (good idea) allowing for additional tactics/skills, like magic (Tasha's Hideous Laughter, woohoo).
In Icewind Dale 2 (or any other IE game for that matter, but IWD2 is my favourite of them) you would basically rely on a "archers weaken giant enemy for fighters to then kill off without taking too much damage" strategy. That's not to say it's lame, but it's nowhere near as intricate, precise, or tactical as the ToEE variation where you really must compete against a giant in the PnP way - that is, outsmart him/her using superior intelligence and planning. The game was originally set up for a motley brand of clever adventurers to go up against physically over powered enemies that are shallow fighters. There should very rarely be a case of "we take turns hitting each other till one falls" and in ToEE, you could very easily avoid that (admittedly I did often take that route when surrounded by Bugbears), where-as in the IE games you couldn't. At most you could activate a buff, use a crowd control spell/ability, or just keep on hacking/shooting.