Yorick's Graves Feel Bad

After playing new Yorick most this evening, I must say it feels very bad to not be able to produce graves at a decent rate early, or not at all in late game if a team fight breaks out in the river or jungle. Without his Ult, Yorick has no production of mist walkers in a lot of scenarios, this limited him to a very specific niche and creates situations in which he is at a disadvantage far too frequently. His being leashed to minions and monsters for production is clunky and awkward in a game where champions need to be fluid and mobile.

My previous suggestion of summoning graves when Yorick's W wall dissipated or was destroyed was met with a negative response from the designer. Perhaps another solution could be found instead, one in which he makes graves while Q is on cooldown but no more than 4 per 30/20/10s? Instead of last hitting with Q to make them he just gets them while it is cooling down and gets charges of souls to dig graves for at a fixed interval. This solution allows him to have ghouls on demand, and set up a good feed of them for sieges later, while not being too oppressive in the early game. Further this uplinks his need to last hit with Last Rites and may then use it more frequently for trading.

I really doubt anyone from Riot will read this or care honestly, but I wanted to try to figure out a different approach because being leashed to minions and monsters limits the gameplay to very static routes that are less fun. There have already been several situations in which I needed to grab some farm from a side lane just to go group up with my team with some mist walkers beside me, and it was far too late by the time I got there. There is no situation currently in which this feels good, the preparation time is too extreme, without the Maiden available Yorick doesn't get to partake in teamfights.

For Yorick to ever be a strong pick he is going to need a way to passively generate graves consistently and on demand, or be balanced around not having mistwalkers at all, because he cannot currently consistently generate his required graves to be at full strength for anything past the laning phase. It is not a question of the walkers being durable enough, but whether Yorick can get them up and with him to a fight in a timely fashion.

So, what other solutions can anyone else think of?

Also, Riot if you read this, why design the passive in such a way that keeps Yorick from having Mistwalkers when he needs them most?