Howard County stays in MD under my plan. If we gave Howard County (which is quite Democrat-leaning) to New Columbia then we might as well give them Baltimore city (and at least part of Baltimore County) as well, and if we took Baltimore away from MD then what’s left would not really be MD anymore.
HoCO is pretty Dem but not as bad as MontCo or PG - and MD could still go relatively reliably Republican with it if MontCo and PG were out of the equation.