The default vanilla Engineer is capable of being a supersoldier unto himself, can carry enough equipment to build a sizable city without it impeding him in the slightest, crafts as fast as an assembling machine 2.5, and mines as fast as an electric mining drill - twice as fast once you get a steel axe. Additionally, they can teleport items to themselves from a significant distance away, and similarly alter instructions for machines from a distance. The Imperfect vision adjusts this to require the Engineer to rely more on their factory:

• Encumbrance is a thing. Movement, crafting, and mining are all reduced if there is a significant amount in your inventory.
• Crafting and Mining are both slashed to one-fourth their vanilla capabilities, making the Engineer half as fast as a burner mining drill or assembling machine 1. Trees are not included in this, since there's no early-game method for automating wood collection.
• If playing Imperfection or Imperfection Complete, 'Short Reach' is in place; default reach of the Engineer is reduced.
• The Toolbelt and Steel Axe technologies have been removed.
• Mining all structures is basically instantaneous. Waiting a reasonable time for this is not something that really adds any compelling logistical considerations in my opinion, it's just ... waiting for waiting's sake. Also, construction bots are going to do it instantly anyway and they can't be given any sort of mining delay from what I can tell. I considered a delay on placing structures and rejected it for similar reasons. The only aspect it would really be useful for is combat with turrets taking longer to place, and given that Imperfection is meant to be played without enemies, well ...
• Settings are naturally included for adjusting most of these factors.