I would raise the age requirement to 21, unless the person has gainful employment and/ or lives on their own or pays rent... I believe working for a living sobers one up, especially when you see how much in taxes are taken out by local, state, and federal taxes. (but then, I would also eliminate the draft as well, except in national emergency, and exclude only sons even in NE.)
Why allow them to hold office if they can't vote?
So were the 16th 17th &,18th https://blog.independent.org/2013/02/12/the-16th-amendment-a-transfer-of-power-from-the-states-to-the-federal-government/ I think the 16th, 17th and 18th were actually bigger mistakes, but that's MHO. https://conventionofstates.com/news/effect-of-the-seventeenth-amendment (this covers the 18th, as well and 19th. ) The 19th was more easily justifiable, as it was presumed that wives and husbands would share similar values.
Agreed to some degree, but not fully. However, I surely would prefer to maintain my right to vote, since my husband and I co-own property. Also, if two are working in a household, even if one is working part time so as to care for /homeschool children I believe that sort of woman is more qualified to vote than an unemployed single person who owns nothing (regardless of sex or age).
And this is backed up by history from the Revolution on. There have always been women on the field, caring for the men who are wounded (Florence Nightingale and others) Molly Pitchers, keeping water handy where needed, or actually fighting (Deborah Sampson and others).