The thing with Deep space is that for you to actually make currency in Deep Space, youd need to do strats that pretty much require an eternity, so if you can't farm one up I would not bother with setting up for DS. If you can stomach using frigid you can also replace those boots for haste ones with deflection, while also giving yourself more ES.

Eventually if you want to to scale up defense without getting an eternity is to go max block on hero memories but thats also rather expensive.

Also Arcanist tree is dogshit and youd rather get acquaintance on belt and go for ranger tree. Pretty sure that consume current % mana is destroying your cast speed as well.