I'm going to go ahead and make a few assumptions about what you have access to. I'm going to assume at least ambuscade hallmarks, T2 Escha Ru'aun. Possibly Delve. And a few Reisenjima T1s (Valorous Mask is pretty easy, if the others aren't). Here is more or less what I started with.
Starter TP:
ItemSet 358379
Augments:
Cibitshavore: 12 STR racc 7 STP path. This is from delve, its excellent until you have access to some of the good ammos for SAM.
Smertrios: 20 DEX 20 acc/atk 10 DA or 10 STP depending on what you need. (Up either DEX or acc to 30 later)
Ryuo Hakama: Path D gives acc and STP
Ryuo Sune-Ate: Path A or B (acc) or path C (STP)
Alternatives:
Grip:
bloodrain strap/
nepenthe grip
Ammo:
Ginsen (acc/STP) or
Paeapua (TA) can be good
Ears:
brutal earring/
cessance earring/
telos earring/
dignitary's earring, theres a lot of alternatives
Body: AF+2 is good, Ryuo is good, but Kasuga Domaru +1 is probably BiS right now.
Rings: Lots of options, I like K'ayres because of the HP that comes with the STP.
Back:
takaha mantle if you get a +Zanshin augment on it is good.
Feet:
flamma gambieras +1 if you don't do Ryuo.
Required:
Wakido Kote +2: This is a must, the +3 Hasso is really good, on top of good acc and STP
Starter WS:
ItemSet 358380
Augments:
Cibitshavore: Same as above, it's locked in place if you're using it.
Valorous Mask: whatever you can get of +WSD, +acc, +STR in that order imo. Goal of 10 STR 30+ acc 5% WSD (fern) or 15 STR 30+ acc 4% WSD (taupe). Atk is nice, but much less important than other stats. I included this one because it's significantly easier to get than other valorous pieces.
Smertrios: 20 STR 20 acc/atk 10 WSD (up STR to 30 later)
Alternatives:
For starter set, there aren't a ton of alternatives here that aren't starting to get into more mid-range/endgame sets.
Hizamaru Mask +1 instead of Valorous Mask until you get one.
Hizamaru -> Flamma Set if you want STP, which might be better than what I've got there now. You lose a lot of attack though.
Required:
Again, nothing here is really "required" for the starter build. Almost all of this is going to be replaced eventually except for Smertrios
Goal: Enough STP in this build to give your TP build specific TP/hit. This set is really light on STP. Expect (0 JP) 180 TP return from WS or 193 if you have aftermath from Amano.
With this build, you need 83 STP for a 4-hit (WS + 3 hits). With 10 STP on smertrios and STP Ryuo you've got 75. So 4-hit isn't viable unless you're using Kaiten for aftermath. or you keep your STP in your ring slots probably.