In my experience a lot of money is expended on trying to make a rifle shoot better BEFORE the shooter has exceeded the capabilities of the rifle "As Is". You've got a pretty good setup there and I'd just hit the range and practice, practice, practice.
Focus on basics like position, grip, technique (like preloading bipod before each shot, squeezing trigger the same every time, etc). When you've reached the limit of accuracy then it's time to make changes. If shooting factory ammo it might also be time to start hand loading. Again, work on your loading technique until you've reached another plateau in accuracy.
Usually the first two changes that are made after you've hit a plateau is the trigger. Next is the stock unless the original was so crappy it hit the barrel with every shot.
As for the Howa Trigger, haven't shot one. I will say that about 6 months ago I bought a Savage 10T with Accutrigger and hated it. Nothing like my Remingtons with Timney CE triggers. No replacement available for this model Savage without serious modification to the action so I just shot it as is. Amazing though. After a while I'm actually shooting this rifle as good if not better than my Remingtons.
Last Friday a group at 200 yards measured .107 MOA. Point is that one can get used to something "different" and overcome the perceived "faults".
I know it's neat to get fancier gear, dumping $300-$1000 in a stock and another $100-$400 in a trigger assembly but remember, without a good "operator" it just becomes a very expensive rifle that just shoots "average".