I don't have an opinion to offer on the specialty tools. I don't do enough cakes to add anything of value.
However - I do have a thought on your venue wanting to offer cakes made by their very own pastry chef. Perhaps you and your boss can offer 2 styles of cakes. So, you don't have to stress out over learning every tiny little technique all at once.
I'm not sure if your target market are interested in cupcakes. However, you could offer cupcakes with a topper cake. OR, a 3 tiered cake with fresh flowers and/or ribbon. If you kept it these two offerings, you can perfect the basics. THEN...move on to other trendy techniques and fancy things.
Offering cupcakes is very convenient for a new decorator. With an acrylic stand, a neat presentation is offered effortlessly. With the options out there for great cupcake liners and wrappers...again, it adds to the flawless presentation. For add ons like pretty flowers and pearls, a sheen airbrushed on for sparkle. All these things are easily cut out in fondant, dried and placed on top of the icing. Monogram medallions look very pretty as well. I'm NOT a piper. I have NO desire to learn the basic buttercream techniques. So, I use cutters. Tons of them. You are a pastry chef! Maybe you know some neat things to do with chocolate & sugar for fun garnishes. Do you do anything special for your desserts? Perhaps those things would translate onto the cupcake tops?
For the 3 tier cake. Perhaps you can look into a standardized way of stacking. If you are offering the same 3 tier cake, technically the size and height of the cake would be the same, you can re-use say...hidden pillars and wilton separator plates. Doing the same technique of stacking over and over will build confidence. What about looking into the alternative ways of applying buttercream? Lots of people like the smooth application. I do too. But there are very pretty ways to apply buttercream "roughly" to get an effect. I've seen many that are elegant. So...then you just add fresh flowers.
When I first tried cakes....I went nuts trying this technique and that new idea & I just never got great at any ONE thing. Maybe it's best to offer 2 styles & 2 structures. That way, you are super confident a lot quicker.
THEN...think about adding another variable. Just my 4 cents.