As an artificer you attain bonuses to UMD which compensate to the -CHR you suffer for staying a warforged. In addition, if you have any metamagic feats, they are often applied to scrolls, wands, and many others that you use when in battle or from combat. For your juggernaut, grab https://goliathbarbarian02356.bloguerosa.com/27576194/the-ultimate-guide-to-human-fighter-dnd-5e