Something small and 2 or 4 GB RAM. Raspberry pi's compute power is good enough for me, I'm not doing anything too intensive.
Is raspberry pi 4 still the best answer?
I am a tinkerer and don't mind tinkering. I typically use Gentoo Linux as main OS. I also don't mind ARM or other architectures. I've been eyeing the RockPro64 as well.
NO. SBCs aren't as good as x86 computers, also don’t get server hardware, use regular desktop/laptop machines as they’ll be more than enough for you. Server hardware is way more expensive and won’t be of any advantage. If you’re looking to buy you can even get very good 9-10th gen Intel CPUs and motherboards that are perfect to run servers (very high performance) but that people don’t want because they aren’t good to play the latest games. This hardware is also way more power efficient and sometimes even more powerful than any server hardware that you might get for the same price. Get this hardware for cheap and enjoy.
If you don't require a TON of computer power some people might suggest ARM board, such as the Raspberry Pi, but be careful with those. ARM is great for power savings but compared to consumer hardware is it shit when it comes to performance and reliability. Also I personally like to avoid the Raspberry Pi and their stuff as much as possible. They've done good things for the community however they've some predatory tactics and shenanigans that aren't cool. Here a few examples of what people usually fail to see:
*For what's worth the NanoPi M4 released in 2018 with a RK3399 already had a PCI interface, 4GB of RAM and whatnot and was cheaper than the Raspberry Pi 3 Model B+ from the same year that had Ethernet shared with the USB bus. If you still want ARM and you're about just serving a few websites, cloud service wtv pick a Chinese brand such as friendlyelec or rockpi. More computing for less money and a lot less proprietary BS.
I what would recommend is instead a Mini-PC like the HP EliteDesk 800 G2 DM or the Dell OptiPlex 3050 Micro.
If you plan to create a small NAS for storage and self-host a few services even an old laptop will do it, however there are advantages to picking a mini PC. Those machines are quiet, don't require much power and some can even fit a 2.5" hard drive so you won't need external hard drive enclosures. More on that later.
Mini-PCs are also cheap second hand, you might be able to get an 8th Gen Intel CPU for 100-200€. Sometimes you'll find really old models (i3 CPU + 4 GB of RAM) selling for 50€ and while those aren't usable anymore as a Windows desktop they're are still more than enough to run your NAS/Cloud solution. I would pick something 6th gen or more recent.
For eg. for 100€ you can find an HP Mini with an i5 8th gen + 16GB of ram + 256GB NVME that obviously has a case, a LOT of I/O, PCIe (m2) comes with a power adapter and outperforms a RPi5 in all possible ways. Note that the RPi5 8GB of ram will cost you 80€ + case + power adapter + cable + bullshit adapter + SD card + whatever else money grab - the Pi isn't just a good option. Aside from the big brands like HP and Dell there are other alternatives such as the trendy MINISFORUM however their BIOS comes out of the factory with weird bugs and the hardware isn’t as reliable - missing ESD protection on USB in some models and whatnot.
A very important thing for you to consider is the storage / hard drive interface. On a Pi you're usually constrained to USB for your hard drives, however on a Mini PCs you've the following options:
In both SATA cases you just have to throw NAS hard drives and a cheap power supply at it and you'll be done. SATA is faster and way more reliable than USB for storage, it won't randomly disconnect and you will be able to take full advantage of the disks, no speed limitations like in a typical USB connections. Personally I would pick model that has both the SATA connector and the NVME slot and then use the SATA connector for a small 2.5" SSD (boot drive) and the NVME with the adapter above for the NAS hard drives - this option will give you the best performance.
tldr: don't waste money on a Pi, get a Mini PC instead that comes with more stuff out of the box and way more performance / stability.