Struggling with Qwen3.6 27B / 35B locally (3090) slow responses, breaking code looking for better setup + auto model switching

Hey everyone,

I’ve been experimenting with running Qwen models locally on my setup:

GPU: RTX 3090 (24GB VRAM)

RAM: 64GB

CPU: Ryzen 5700X

OS: Windows 11

What I’m currently running

Qwen 3.6 35B (UD Q4_K_M)

llama-server.exe -m "C:\Users\Dino\.lmstudio\models\unsloth\Qwen3.6-35B-A3B-GGUF\Qwen3.6-35B-A3B-UD-Q4_K_M.gguf" -ngl 99 -c 131072 -np 2 -fa on -ctk f16 -ctv f16 -b 2048 -ub 512 -t 8 --mlock -rea on --reasoning-budget 2048 --reasoning-format deepseek --jinja --metrics --slots --port 8081 --host 0.0.0.0 

Qwen 3.6 27B (UD Q4_K_XL)

llama-server.exe -m "C:\Users\Dino\.lmstudio\models\unsloth\Qwen3.6-27B-GGUF\Qwen3.6-27B-UD-Q4_K_XL.gguf" -ngl 99 -c 196608 -np 1 -fa on -ctk q8_0 -ctv q8_0 -b 2048 -ub 512 -t 8 --no-mmap -rea on --reasoning-budget -1 --reasoning-format deepseek --jinja --metrics --slots --port 8081 --host 0.0.0.0 

My use case

• Hermes agent (on Raspberry Pi 5) → Reddit scraping, job scraping, basic automation
• Local coding (OpenCode / QwenCode) → small scripts, debugging, patching
• Occasional infra setup via prompts

Issues I’m facing

• 35B is too slow
  • Even simple tasks take way too long to respond. Feels unusable for anything iterative.
• 27B is faster but unreliable
  • Code often breaks
  • Takes 20–30 mins even for simple tasks sometimes

What I’m looking for

1. Better model + quant recommendations
   • Something that actually works well on a 3090
   • Good balance between speed + coding reliability
2. Ways to improve throughput (t/s)
   • Are my flags bad?
   • Context size too high?
   • Anything obvious I’m missing?
3. Auto model loading / routing (Right now I have to):
   • Kill server
   • Paste new command
   • Reload model

• Is there a way to:
  • Auto-switch models based on request?
  • Or keep multiple models warm and route between them?

What’s your stack?

Thanks in advance for any suggestions or help really appreciate it.