For use as a stand alone tower, th e 4-high bits on the corners would be unusual IRL (at least until gunpowder initiated the chain of evolution leading to the star fort)… on the other hand, mc doesn't have seige weapons so the design constraints are quitre different.

Adding a few loopholes/arrowslits might help with both appearance (and function vs pillager patrols).

Adding battements to any fighting tops would be a fairly easy way to provide a medieval appearance, although you might want to plan out the block count to try and keep the merlons all of the same size. (If that doesn't come out 'hiding' any excess at the corners or over a gate or door may work.)
[​Merlons are the bits tha stick up, with the openings between referred to as crenels when the wall top is embattled i.e. goes █▄█▄█▄█▄█ ]

It looks like you may already have the start of machicolations (a narrow projecting of the floor at the wall that would have occasional holes [​generally with covers – e.g. trapdoors in MC-speak] that would enable defenders to drop or shoot things at attackers at the base of the wall)…

Lookout towers (usually wooden) were also fairly common as one would signifcantly extend the area that could be surveilled at minimum cost.

Beyond that, clearing the nearby trees (both for visibility and to deny an enemy a lookout perch) and landscaping to avoid holes in which an attacker could hide might be worth considering. [​The formal glacis (which was sloped to maximize the effect of cannon) was a late innovation, but the cleared area (the beginnnigs of the modern concept of "lawn") began quite early — being used to graze sheep in at least some instances.]


Hope that gives you some useful ideas and lok forward to seeing your finished build.