Building own cage- plastic vs wire

I was going to use some sort of plexi glass or some type of plastic sheeting... is this better than wire screen for cleaning purposes.

Cleaning purposes aside, wire screen is suitable for a very small number of species, primarily chameleons and a few other lizards.
What are you intending on housing in the cage.

it depends on what your housing mostly likely plastic unless your housinh chameleons how are very susceptible to respitory disease and with wire your taking a chance of toes getting caught with larger reptiles unless you use a fine mesh wire

I was going to use wire only for the front. I would use something else for the bottom. Im going to house a snake. I guess wire would not be good if I need to keep the air temp and humidity level at a certain degree. Im not sure what kind of snake im getting but if i did use wire and need to keep the cage around 77-87 degrees would a light keep it at that temp if using wire?

A wire front is not suitable for a snake cage. Aside from the heat and humidity issues, the snake will most likely push on the wire trying to get through it and can suffer damage as a result. They are not as prone to do this with very fine mesh like window screening, but anything larger like 1/4" hardware cloth will make them try to push through it.
Using a light to keep the temps up in a cage with that much ventilation will keep it so dry maintaining the humidity will be nearly impossible.