Images, including those put up during Mary's reign, were destroyed - only some stained glass was left untouched, perhaps because of the expense of re-glazing broken windows. The most symbolic change, however, was the replacement of the great rood above the screen with the Royal Arms.
'There was very little new building during the late 16th and early 17th centuries ...'
In part this was because roods had been a focus of pre-Reformation devotion, and therefore were idolatrous, but it also served to emphasise that the Church was now part of the state, with the monarch as its supreme head.
There was very little new building during the late 16th and early 17th centuries, but much money was spent on adapting older churches to the new ways. At Hereford Cathedral, for instance, more than £29 was spent in 1588 on 'seats in the bodie of the church [nave] for the more convenient hearing of sermons'. Precisely what inconvenient arrangement this replaced isn't entirely clear - presumably there were no seats at all in the nave and everyone had had to stand.