Youngster Josh detailed ranges

Level 10 for Roxanne's Geodude (RT rolls change)
9- / x / x				13			18–21 / (22)
10–19 / x / x			14			(16) / 18–19 / (21)
20–29 / 9- / x			15			16–18 / (19)
30+ / 10–29 / 19-		16–17		15–16 / (18)
x / 30+ / 20+			18–19		13–15 / (16)
Level 11 for Roxanne's Nosepass (Tackle rolls change)
8- / x / x			14			8–9 / (10)
9+ / 17- / 8-		15–17			7–8 / (9)
x / 18+ / 9–26		18–19			6–7 / (8)
x / x / 27+			20			(5) / 6 / (7)

With 27+ Sp. Atk (28+/10+/0+), Water Gun* x2 12.1% 2HKO

Level 12 for Clark's Geodude (Rollout rolls change)
7- / x / x				15			(7) / 9 / (10)
8+ / 15- / 7-			16–18			7 / (9)
x / 16+ / 8+			19–22			6 / (7)
Level 13 for Grunt Pooch
Outspeed with 15+ Speed (13+/0+/0+)
Guaranteed 3HKO with Water Gun
Rock Tomb 2HKO:
0.4% 		24 			x/10-13/x
18.8% 		25-26 		x/14-29/0-13
75%			27-28		x/30+/14-29
100%		29			x/x/30+
Water Gun 2HKO:
0%			18-19		17+/0-15/0-7
0.4%		20-21		x/16-30/8-15
37.1%		22-23		x/31/16-30
100%		24			x/x/31

Level 14 for Hideki (!) (defensive ranges shift, offensive ranges shift, more likely to outspeed)
Outspeed before Low Sweep at 18+ Speed (27+/12+/5+)
Low Sweep Ranges:
6- / x / x				17			18–21 / (22)
7–20 / x / x			18			(16) / 18–19 / (21)
21+ / 13- / 6-			19–20		16–18 / (19)
x / 14–27 / 7–13		21–22		15–16 / (18)
x / 28+ / 14+			23–25		13–15 / (16)
Echoed Voice x3 ranges (including crit chances):
46.9%		at	18		8–21 / x / x
81.5%		at	19		22–28 / 7- / x
93.6%		at	20		29+ / 8–14 / 7-
100%		at	21+		x / 15+ / 0+
Level 15 for Brawly's Machop, more likely to put in heal range with Silk Scarf on (skip taking it off)
Marshtomp for Grunt 2
	- Outspeed Zubat at 21+ Speed (18+/0+/0+)
	- Always OHKO Zubat Rock Tomb
	- Outspeed Carvanha 2 at 24+ Speed (x/18+/6+)
	- Carvanha Soft Sand Mud Shot:
	18–23 / 4- / x			24				5 / 16
	24+ / 5–17 / 4-			25–26			8 / 16
	x / 18–23 / 5–11		27				12 / 16
	x / 24–29 / 12–17		28				15 / 16
	x / 30+ / 18+			29–31			16 / 16
+1 Plusle Soft Sand Mud Shot:
18–29 / 11- / x			24–25			7 / 16
30+ / 12–23 / 11-		26–27			12 / 16
x / 24+ / 12+			28–31			16 / 16
+1 Minun Soft Sand Mud Shot:
10–21 / 3- / x			24–25			7 / 16
22+ / 4–15 / 3-			26–27			12 / 16
x / 16+ / 4+			28–33			16 / 16
Level 18 for Rival 2 Slugma
Incinerate:
14- / x / x			27–28			9–10 / (11)
15–25 / 3- / x		29–30			(8) / 9 / (10)
26+ / 4–20 / 3-		31–33			8–9
x / 21+ / 4–20		34–36			7–8 / (9)
x / x / 21+			37–38			6–7 / (8)
Level 21 for Wattson's Magneton, outspeed with 0-1 neutral speed
Level 22 for Wilton's Bagon, slightly better 2HKO
Bulldoze x2 ranges:
99.6%		at	44/45	(x / 6-14 / x)
100%		at	46+		(x / 15+ / 0+)

OPTION TO PP-UP SKIP!
Skip Rustboro Mart, get/skip Super Repel
Skip PP-Up

In Slateport, buy:
Top
		6 X-Speeds				5 if Speed is  (x / 28+ / 16+), 7 if Speed is (22 - 26 / 5 - 8 / x)
		8 X-Attack (v)
		1 X-Defense (v)
		4 X-Sp.Atk (>^^)		3 If buying 7 X-Speeds

Bottom
	4 Super Repels (^^)

With this shopping, you won't have a spare X-Attack for Archie and the Rival 2 fight will be different (detailing below)

Rival 2:
Slugma: X-Speed x2, Echoed Voice x3
Grovyle: Echoed Voice x2
Wailmer: Echoed Voice x2

You can do this fight without Silk Scarf (i.e. if you already have Soft Sand on) and you only risk the one turn on Grovyle.