I reckon there is great scope to formalise the exisitng Yarra trails as multiuse (multidirectional), to have a ‘foot in the door’ with Parks on how great to work with & active park users MTBers are, as well as how flexible these existing trails can be for the use of the greater local community.
Then there can be a step to introduce a MTB-specific trail (one-way loop for example) in an area off this trail network, using an area currently not used for anything else. This can become slightly more technical trail with some built obsticals, so casual riders have the option of skipping it.
With locations close or in medium to high dencity areas like Yarra Flats etc, I think it’s important not to commandeer existing trails for MTBers only, because it’ll make everyone else feel the same way I do when the “No cyclist” signs were up at either end of the trail opposite the Fairfield boathouse.
On another note, the log barrier alongside the golf course/freeway has been sawn off, with what looks like timber placed at the base of the step down. Do riders actually ride off this step down? I’ve looked at it & taken the dismount, chuck the bike off it & remount approach instead.