The cubs have more pitching than people realize in their system. It is clearly overshadowed by the hitting and the fact there is no top 25 prospect. With that being said, Pierce Johnson still has #3 tools and should start in AAA next season with a chance to be fast tracked by midseaosn. Edwards probably starts in the bull pen given how they have approached this season with him but you never know. Those are the only two decent names at the high level.
A year from now Duane Underwood might be a top 30 prospect. Hell, mlb.com has him #67 right now. I'm guessing he starts next year in AA but he could also start in A+ with an eye toward a quick promotion depending on other players. That puts him 2-3 years out but he truly does have TOR stuff if everything comes together. Then you have Dylan Cease who throws 97 with a decent curve. He's more like 4-5 years away but he's a legit prospect. Bryan Hudson they drafted in the 3rd this past draft is on a similar time frame and has 2 plus pitches. It falls off a little after that. Justin Steele, Jen-Ho Tseng, Jake Stinnett, Oscar De La Cruz, Rob Zastryzny, Trevor Clifton, Daury Torrez, Jeremy Null and Ryan Williams are all still legit prospects but probably more #3-5 starters. Carson Sands I think from what i've read could fall into either of the two groups I mentioned but at the moment he's not been that amazing.
The thing about pitching is guys will often just come out of no where and suddenly be top prospects. Typically the higher rated guys are college guys who get drafted just because among pitchers they are more "sure things." But using Underwood as an example, I don't even think he was in mlb.com's top 15 cubs prospects before this year.And it's not even a case of him being a low pick that shot up. IIRC he was a 2nd round pick. You look at another guy like Steven Matz from the mets system and he was the met's 29th ranked prospect after 2012 according to BA, their #12 prospect after 2013 and their #2 prospect after 2014.
So like I said, it's not really that they lack pitching. It's more that they lack MLB ready pitching. And the thing is you have a #1/2 assuming they lock Arrieta up. So, this doom and gloom about getting a young stud is a bit much. If Johnson comes up at midseason and pitches like a #3 your 1-4 is probably one of the best 1-4 in baseball or at the very least top 5. I have mentioned this a number of times but the cubs starter fWAR was the highest in the majors. Their starter ERA was 3rd in the majors behind the Cardinals who had a statistically absurd year and the Dodgers who had 2 of the 3 Cy Young candidates. The cubs starters were second to the indians in k/9. They were 3rd behind the mets and nationals in bb/9. They were 1st in FIP. Just to be clear here.... we're talking about a team who basically was piecing together a #5 starter for most of the year and they still put those numbers up.
Long story short, the cubs don't need David Price to have a great staff. If they got another pitcher basically on the level with what Hendricks gave them they would have a phenomenal staff albeit greatly under appreciated by the media and most fans. Given the ridiculous amount of depth in starters in FA you could very realistically sign someone like John Lackey for $10-15 mil/season for say 1-2 years to get you by until your younger pitchers are ready. Trades are always an option but it isn't like they have to deal to make it work. With that being said, they have a number of lessor prospects who are rule 5 eligible so it wouldn't shock me that much to see one or two smaller trades for various parts. Guys like Vogelbach, Corey Black, and Daury Torrez are possibly guys who won't fit on the 40 man and you may choose to deal instead. They probably need to make a choice on either Christian Villanueva or Jeimer Candelario in the offseason as well considering Baez may end up having to play 3B and even if he doesn't, you have Bryant and those two will be fighting each other for time in AAA likely by the end of next season.