So it is a good practice to have a variety of wallets then?
For example,
Laminated paper wallets kept in a secure place - for long term storage (6 months and above)
Hardware wallet like Nano Ledger - for day trading (Qs: How often do you deposit/withdraw funds from exchanges into this wallet?)
Mobile wallet - For small misc transactions
or if you want to use it to make purchases, then you won't really do it with 10, you do it with smaller so put that smaller amount (like 0.1BTC) in a place where you can access it easily. it can be your desktop wallet, your phone or if you really needed it a web wallet but that should be the last resort.
When it comes to "splitting" assets into smaller amounts, can you explain why you should do so, and
how/where you will split them? If it is for security, how does splitting them help? If it is for convenience, I feel it is counter-productive. Or is it related to cost of transaction in some way?
it is mostly preference, but also both security and convenience at the same time. it is up to you to choose which method(s) suits you the best and makes you feel more comfortable. for instance there are people only have a hardware wallet and do all their affairs with that and are happy with that set up.
i personally have a hot wallet on my desktop and a cold storage (self made using Linux and encrypted) on a USB disk using Electrum. then i have my seed written down on a paper as an additional backup in case the USB was damaged/lost,...
and the way "I" do it is that i only keep a certain amount in my hot wallet and after reaching the threshold i transfer them to my cold storage. and the hot wallet is used to receive payments, spend bitcoin, sell some if i needed money, trade altcoins with,...