All your examples are EXPLICITLY IN the Constitution
1) The govt. drafts people and puts them in harms way all the time.
Its in the Constitution - Article I Section 8 "militia clause"
2) The govt. forces people to pay taxes, for many against their will.
Taxing assets is not involuntary servitude. The Government cannot force you to donate blood for example, to pay for your outstanding tax bill. Furthermore to get around the Am 4 restrictions on seizure and the Am 5 "takings clause" BOTH of which precluded taxation the Constitution had to FIRST be amended to cede to Government the power to collect income tax. Its called the 16th Amendment
3) Unwilling fathers are forced to pay child support.
This is a tort claim that comes about only after Due Process. Since Am 5 and Am 4 requirements have been satisfied settling tort claims IS part of The Governments power (Article III Section 2). Note though, that Amendment 13 precludes The Government from forcing the father to work, or to donate blood to pay for that child support. It is purely a civil tort that satisfies Due Process and Reasonable Seizure clauses.
4) There seems to be more common law than admited to in the past regarding abortion and its prohibition.
So what? More is not sufficient. CONSISTENT is required.
That abortion currently IS regulated is a consequence of the weakness of Roe, not out of any inherent Constitutionality of those regulations. And in the long run it will go down the same path as the poll tax.
Repeat abortion seekers simply indicate that they repeatedly seek abortions. It has no bearing on whether or not abortion can or should be regulated any more than the continuous need for blood and organ donation means that The Government should be given the power to demand you give up a kidney "to preserve life".