Just disable those you have no use for. You'll get a warning message, but that's boilerplate. If an app is genuinely vital the system won't let you do this, so if you can it should be safe (sadly some real junk might also be protected against disabling - some carriers do this).
There is no functional difference between disabling and removing: the app can't run, its data and updates are removed so it uses no space (the original app is in a different partition, so doesn't use user-accessible space). But it doesn't require root, and can be reversed if you need to.