I am still not convinced on the whole lineage points and Uzumakis not inheriting anything from him as his powers were split in two. It would have been more logical for him to be Uzumaki if both Uchiha and Senju were linked to the said clan; as both of the are technically distant cousins as well. This one-sided connection of Uzumaki is what puts me off. If the manga goes down this route, then I will be disappointed as it wouldn't have any sense to me in regards to Gemini division of Sage through his two sons.
Madara killing Uzumaki clan to preserve his moon's eye plan seems quite far-fetched to me. Hence, I am disagreeing with this point altogether. Perhaps he killed/eliminated them to weaken Senju clan as both are tied by bond and create less resistance but not for the reasons you posted, as their strongest sealing Jutsu can be undone via Uchiha Tablet, I cannot see Uzumaki clan doing any than this.
But, great effort regardless.