This might be the memest of meme builds, but please bear with me while I spew nonsense:

• Null's Inclination Bow: 1% minion damage per 5 dexterity, plus trigger minion skills on bow kill.
• Speaker's Wreath: Minion attack and movement speed per 50 dexterity. Plus makes it harder for minions to outright kill things which will help trigger Null's Inclination.
• Rupturing and Ungil's Harmony: Your crits apply rupture, which globally increases bleed damage, including from Reaper.
• Gathering Winds and Focal Point: Apply to your minions by offering general support. Use a Poacher's Mark ring with Focal Point to sustain life and mana while giving more flat damage to Reaper for big bleeds.

Link Vaal Skeletons and Flesh Offering in Null's Inclination. As your main skill, Ensnaring Arrow with Faster Attacks, Increased Crit and Culling Strike (since its sole purpose is to apply the "moving" debuff and trigger Rupturing by critting as fast as possible, as well as triggering Null's through culling hits). Get Kineticism to ensure ensnares always stick and hold enemies at bay.

Your entire role is to spot for the reaper and debuff enemies through a combination of improved Marks, three-stacking Rupturing and maintaining the "is always moving" debuff, while your Reaper goes to town. In the meantime, Skellies and offerings are popping out from Null's triggers (aided by a writhing jar against bosses without adds).

Since the build benefits from stacking dex, there isn't much problem with traveling far out of the ranger area to look for minion bonuses elsewhere as long as you stick to green tracks.

Whether this is decent or an absolute joke will depend on Reaper numbers, but you can't deny it sounds fun.

EDIT: Here's an initial PoB as a starting point; probably pretty rough since I did it quickly, and obviously missing the Reaper gem, but you get the idea https://pastebin.com/PiVTa6mr