Using loans from higher tiers to cover your weaker positions is great. In particular I prefer to try and bring in a higher tier Central Mid Playmaker (DM / CM / ACM) regardless of what central players I have.
Because of the part time training I generally only have 1 or 2 tactics in training. During pre-season I usually only have the 1 as it seems to help them learn it better, but I stick with what the backroom staff suggest.
Another good option for sorting out a tactic though is to sort all your players by their Current and Future Potential, with the view set to Assistant Reports. This will give you what your Assistant things their best position and role is, then I use that to make a formation using the best players. From there I then start to tweak, as it is possible to end up with unfavourable partnerships, eg: 2 CM's both with Ball Winning Mid - Support, which isn't going to work well.
Also for LLM I prefer not to set too many instructions, generally I only set the line and tempo I want to play, maybe with keep possession. I will tinker with this during the game, partly from my Assistants suggestions.
As the season goes on making changes to the tactic is a must, even setting up the 2nd and maybe even a 3rd. This way you can start training the team towards a tactic that you want to play, but also stop you from becoming predictable for the AI.
Good luck, I have had some memorable saves with Stockport in the past, I think my best was in FM13.