Chris Lamb has a good Debian installation checklist, from which I stole most of this list.

   1 # Configure sudo, adding my user to the sudo group so I don't get password prompts
   2 apt install sudo
   3 adduser xjjk sudo
   4 echo '%sudo ALL=(ALL) NOPASSWD: ALL' > /etc/sudoers.d/No-Passwords-for-sudo-Group
   5 chmod 0440 /etc/sudoers.d/No-Passwords-for-sudo-Group
   6 
   7 # Disable installation of recommended packages
   8 echo 'APT::Install-Recommends "false";' > /etc/apt/apt.conf.d/90recommends
   9 
  10 # Configure locales to prevent harassment about it later
  11 apt install locales
  12 dpkg-reconfigure -plow locales
  13 # …or install all locales so they don't need to be configured/reinstalled
  14 apt install locales-all
  15 
  16 # Enable log compression with date suffixed extension
  17 cat /etc/logrotate.conf | sed "s/#compress/compress\ndateext/" > /etc/logrotate.conf.tmp
  18 mv /etc/logrotate.conf.tmp /etc/logrotate.conf
  19 
  20 # Disable root login—public key access only!
  21 sed -i 's/PermitRootLogin yes/PermitRootLogin without-password/' /etc/ssh/sshd_config
  22 # Allow TZ variable
  23 sed -i 's/AcceptEnv LANG LC_\*$/AcceptEnv LANG LC_\* TZ/' /etc/ssh/sshd_config
  24 service ssh restart
  25 
  26 # Prevent PAM from allowing easily-crackable passwords
  27 apt install libpam-cracklib
  28 
  29 # Install essential utilities
  30 sudo apt install \
  31 openssh-server screen \
  32 rsync \
  33 atool lzma rzip xz-utils \
  34 htop dstat iotop \
  35 manpages manpages-dev \
  36 strace tcpdump lsof \
  37 less moreutils \
  38 mosh \
  39 dnsutils \
  40 vim vim-pathogen vim-addon-manager vim-scripts \
  41 bash-completion \
  42 sysfsutils procps \
  43 vnstat \
  44 unattended-upgrades \
  45 ncurses-term \
  46 molly-guard
  47 
  48 # Optional stuff…
  49 sudo apt install \
  50 chrony \
  51 cpufrequtils powertop
  52 
  53 # Ensure enough entropy is always available
  54 sudo apt install \
  55 haveged rng-tools
  56 
  57 # I hate rm
  58 sudo apt install \
  59 trash-cli
  60 
  61 # Reduce bufferbloat
  62 echo 'net.core.default_qdisc=fq_codel' > /etc/sysctl.d/reduce-bufferbloat.conf
  63 
  64 # Enable automatic security updates (careful!)
  65 sudo DEBIAN_FRONTEND=noninteractive dpkg-reconfigure -plow unattended-upgrades
  66 
  67 # HDD Temperature/SMART monitoring utilities
  68 apt install hddtemp smartmontools
  69 sed -i 's/^#start_smartd=yes/start_smartd=yes/' /etc/default/smartmontools
  70 /etc/init.d/smartmontools start
  71 
  72 # Configure rsyslog for daily archival logging
  73 cat << EOF > /etc/rsyslog.d/51-cron.conf
  74 # Enable cron logging
  75 cron.* /var/log/cron.log
  76 EOF
  77 cat << EOF > /etc/rsyslog.d/99-archive.conf
  78 \$template DailyLogs,"/var/log/archive/%\$YEAR%%\$MONTH%/%\$YEAR%%\$MONTH%%\$DAY%.log"
  79 # Archive logging
  80 *.* -?DailyLogs
  81 EOF
  82 cat << EOF > /etc/cron.daily/rsyslog-archive
  83 #!/bin/sh
  84 # Compress *.log-files not changed in more than 24 hours
  85 find /var/log/archive -type f -mtime +1 -name "*.log" -exec xz '{}' \;
  86 EOF
  87 chmod +x /etc/cron.daily/rsyslog-archive
  88 
  89 # Async logging for rsync (commit every 30m)
  90 cat << EOF > /etc/rsyslog.d/98-async.conf
  91 \$OMFileFlushInterval 1800
  92 \$OMFileASyncWriting on
  93 EOF
  94 
  95 # Use tmpfs for /var/run and /var/lock (may break some buggy packages), like Ubuntu
  96 cat << EOF >> /etc/default/rcS
  97 RAMRUN=yes
  98 RAMLOCK=yes
  99 EOF
 100 
 101 # Allow running X11 apps remotely
 102 sudo apt install xbase-clients
 103 
 104 # Add noatime,commit=900 to entries in /etc/fstab
 105 
 106 # Enable SATA ALPM
 107 echo SATA_ALPM_ENABLE=true | sudo tee /etc/pm/config.d/sata_alpm
 108 
 109 # Switch to systemd
 110 sudo apt install systemd-sysv libpam-systemd

Other sources:

https://feeding.cloud.geek.nz/posts/usual-server-setup/

New account setup

Remote

   1 # Quiet login
   2 touch .hushlogin
   3 cd ~
   4 mkdir -p .ssh/controls
   5 mkdir -p .vim/tmp
   6 chmod -R 755 .ssh
   7 chmod 644 .ssh/authorized_keys

Locally

   1 # Setup dot files
   2 mkdir -p ~/src/git.other/
   3 cd ~/src/git.other/
   4 git clone https://github.com/samatjain/dotfiles.git
   5 cd dotfiles
   6 source init-dots
   7 dots groups set base # Set addtl groups as necessary
   8 dots install

Raspberry Pi stuff

   1 # Switch from wheezy to testing
   2 cd /etc/apt/
   3 sed -i 's/wheezy/testing/g' /etc/apt/sources.list
   4 #sudo find . -type f -exec sed -i 's/wheezy/testing/g' {} \;
   5 
   6 # Disable tty2–tty6
   7 sed -i '/[2-6]:23:respawn:\/sbin\/getty 38400 tty[2-6]/s%^%#%g' /etc/inittab
   8 # Disable tty on serial line
   9 sed -i '/T0:23:respawn:\/sbin\/getty -L ttyAMA0 115200 vt100/s%^%#%g' /etc/inittab
  10 
  11 # Optimize mounts
  12 sed -i 's/defaults,noatime/defaults,noatime,nodiratime/g' /etc/fstab
  13 
  14 # Overclock to 800 Mhz (no overvolting required). Overclocking not forced, but keep it on for the first 2 min during boot
  15 echo -e "arm_freq=800\nsdram_freq=400\ncore_freq=300\nforce_turbo=0\ninitial_turbo=120" >> /boot/config.txt
  16 
  17 # Use only 16 MiB for GPU (only run after updating firmware!)
  18 echo -e "gpu_mem=16" >> /boot/config.txt
  19 
  20 # Enable IPv6 for Avahi
  21 sudo sed -i 's/mdns4_minimal/mdns_minimal/g' /etc/nsswitch.conf
  22 
  23 # Delete default 'pi' user
  24 sudo deluser --remove-all-files pi

Some of these are from Raspberry Pi Raspbian tuning / optimising / optimizing for reduced memory usage