If you are going to feed the dipole with coax, there is no balun ratio that
would work over the whole range.

If you must use coax, you may also want to look at getting some of the
highest impedance coax you can find.

I humbly and apologetically decline to comment and, hereby, of course,
deviously venture obliquously to imply that the customary norm of duly
perusing an interrogative ponderation, previously consigned to a
written medium of unrestricted admittance, ahead of proffering a reply
thereto, which in turn will be inscribed for posterity to gape at,
cannot wantonly be construed to be peculiarly fraught with some
unnamed yet capital order of detriment. :-)