Samsung S5 G900F ROMS Questions

Hi everyone I need your opinion and suggestions regarding ROMS on this device.
I have Samsung S5 (SM-G900F ) and still confused on what ROMS should I get.
Therefore I need your suggestions and ideas my knox was 0x1 without doing anything.

My questions are:
• For STOCK ROM + Custom Kernel which is a good combination of stock ROM and custom kernel?
• For CUSTOM ROM + Custom Kernel which is the most stable and smooth one?

Currently using Sixperience V7 + Hispasian v7 but it is kinda laggy and buggy as of now.
I am a big fan of doubletap2wake so I want those custom kernel and compatible ROMs that support it.

Thank you for those who will notice and answer my questions.

mixed s6 rom ported to s5 (g900f) with all features of s5 and s6

Hi all

I'm not a developer but I would try to port new s6 firmware to s5,but with all features of s5 (especially the air gesture and air view) and all features of s6/s6 edge like people edge,systemui ,settings etc.

about you is possible?and if YES,who can help me?

I need a stable rom

ps:if this is no possible the moderators can delete this post

regards

soft-bricked galaxy s5 g900f

My s5 g900f recently started having this weird battery issue where the battery would go from 100% - 0 in under an hour, But before I got to replace the battery I jus woke up one morning n the phone was off, tried putting it on after recharging but all it did was continuously show the Samsung logo and reboot. Got a new battery but no change, plus I only seem to have access to download mode.