Question: Simplify presentation

Suppose I have a matrix representing a magma such as

matrix(n,n, (i,j)->E[i].E[j])

First, if E is a set of integers then . is converged to * for some reason.

Second, is there any way to simplify the presentation of this matrix? I am using subs to simply but I have to essentially hand code every entry which sort of defeats the purpose. Is there any way to present a matrix and then have the resultant simplified as far as possible?

E.g., subs does not allow one to do something like ?.E[3] = E[2] where ? represents any value. E.g., if I have an identity it would be nice to simplify all elements quickly with one expression rather than having one for all possibilities(essentially 2n).

Also, magma's only let positive integers which seems kinda restrictive(why not create map internally to handle it?).

Also, is there any way to use special chars like -? I'm using d but I'd prefer using special chars so it is visually more congruent to what I'm doing. I realize - is also a minus but maybe there is someway around it(unicode?)?