When comparing PuTTY vs Alacritty, the Slant community recommends PuTTY for most people. In the question“What are the best terminal emulators for Windows?” PuTTY is ranked 7th while Alacritty is ranked 10th.
Ranked in these QuestionsQuestion Ranking
Pro De facto standard client for SSH, Telnet and Rlogin
PuTTY is one of the oldest and most popular clients. It has earned the trust of a great number of users over a long period by being reliable, offering useful features and helpful support. It got into the 15 Essential Open Source Tools for Windows Admins list by InfoWorld.
Pro Source code available
Full source available. Compile and modify it yourself.
Pro Lightweight and portable
Doesn't require much resources (memory and hard-disk). Can even be run on a system by just downloading without install.
Pro Can be used on any Windows computer, even without admin rights
Pro Blazing fast rendering with GPU-accelerated
Written in Rust with a philosophy focusing on speed and simplicity, Alacritty is one of the fastest terminal emulators out there.
Pro Comprehensive font options
Alacritty can be configured to adjust line spacing (height), letter spacing (width), and individual character horizontal/vertical positions.
Pro Looks good
Alacritty looks very slick on Linux, especially with GNOME or i3.
Pro Has support for image previews in w3m and ranger
Con Can not save passwords
Anyway, you can use "PuTTYgen" to generate a key pair, then use "Pageant" to do a password-less SSH remote login.
Con Lacks features
It is JUST an SSH client. There are many other options with built in X-servers, Multitabbing, etc.
Con Ugly design, too simple
Con Tedious logging/tracing
Its tedious to set up logging and tracing (e.g. for serial connections).
Con No global settings
If you want to change a setting for all your connections, you'd have to do it individually.