Thinking about Giant Fights

This is jumping over to our game set in the Storm King's Thunder. For our last session, we were defending Triboar from a return attack of Fire Giants, looking for a lost fragment. We reached a good stopping point mid-fight, and left the game until our next session, but elements of the whole fight have weighed on me.

On one level, it is everything I've hoped to find in D&D for years... a massive fight in a broad open space... but it drags. Part of the problem is that the encounter is too open. You can spread out enough to protect yourself from a concerted area effect, but at the same time you lose the ability to use any of your own. The same distances that protect you prevent you from effectively targeting your opponent. This leaves a long, dragged out fight as opponents dance around each other and try to nibble away at each other.

In person, these large fights seem to work out better. We've been on Roll20, and it seems difficult to manage some of these larger encounters through that medium. I'm not sure if its an inherent limitation of the technology, or if we're applying in-person logic to the online game, and haven't worked out how to run it more efficiently there. 

I feel like this is the case. Not that the medium is flawed, but that I haven't figured out how to make it work and keep the action vibrant. If we scaled the fight down to moments and drama, it would flow more easily, but I like to play it out fully. Why generate the numbers, stats and HP, unless you plan to use them. But that seems to be awkward online.

We still have half a fight to get through, and I need to find a way to make it flow more naturally. I'm not sure how. That is my task for thought - how to do it. I'll give it some thought...