Having a lot of fun with the mod so far, incredible work here :)
Is it possible to add glider modifier to the chest piece in future update?

Thanks

I too would like to add my voice in requesting a glider add-on. It would be appropriate to have it be a crafted accessory for the chest piece, requiring an elytra and possibly other rare ingredients to craft.

I'm considering it, but I haven't made a final decision on whether to implement something like this or not.

there are many other mods that provide one form of flight to another. I mainly really like how the construct armor looks as well as other aspect of it (leveling, customization) and would rather not wear a different armor simply for their functionality.
Instead of requiring elytra (requires accessing to the end city, which a lot of custom world gen in various mod pack do not have), I think it would make more sense for a more customized recipe similar like Ender IO glider add on for the dark steel armor.

If you do go through with this, (you totally should) could it be a modifier rather than accessory, or at least make it so other accessories can go on with this one as well. Or at least configable whether multiple accessories can be added.

@WGHxPERNAxBEAST
Accessories are created when a potential modifier either 1) needs a keybinding or 2) needs special rendering. It's because of these reasons that allowing multiple accessories on the same item would cause problems, that's why they're mutually exclusive. The glider add-on would need to render the wings at the very least, so it needs to be an accessory.

An Elytra accessory would be pretty fun I think

for this you could use the Colytra mod as a substitute . it basically lets you combine an elytra with any chestplate item on an anvil at the cost of 30 xp levels . so ... no modifier cost and lets you have the accessory as well . and you can configure the elytra to use the chestplate's durability which I highly recommend ( plus its made by TheIllusiveC4 so thats a bonus :) ).